I'm adding this as an answer (even though Michael_B's duplicate addresses the core problem: CSS Grid Layout not working in IE11 even with prefixes ) - even though it's a utility to output multiple rules without having to manually do it.
Here's the output using SASS for the 2-column:
@for $i from 1 through 50 {
dt:nth-of-type(#{$i}) {
-ms-grid-column: 1;
-ms-grid-row: 1 * $i;
}
dd:nth-of-type(#{$i}) {
-ms-grid-column: 2;
-ms-grid-row: 1 * $i;
}
}
This will output:
dt:nth-of-type(1) {
-ms-grid-column: 1;
-ms-grid-row: 1;
}
dd:nth-of-type(1) {
-ms-grid-column: 2;
-ms-grid-row: 1;
}
dt:nth-of-type(2) {
-ms-grid-column: 1;
-ms-grid-row: 2;
}
dd:nth-of-type(2) {
-ms-grid-column: 2;
-ms-grid-row: 2;
}
dt:nth-of-type(3) {
-ms-grid-column: 1;
-ms-grid-row: 3;
}
dd:nth-of-type(3) {
-ms-grid-column: 2;
-ms-grid-row: 3;
}
dt:nth-of-type(4) {
-ms-grid-column: 1;
-ms-grid-row: 4;
}
dd:nth-of-type(4) {
-ms-grid-column: 2;
-ms-grid-row: 4;
}
dt:nth-of-type(5) {
-ms-grid-column: 1;
-ms-grid-row: 5;
}
dd:nth-of-type(5) {
-ms-grid-column: 2;
-ms-grid-row: 5;
}
dt:nth-of-type(6) {
-ms-grid-column: 1;
-ms-grid-row: 6;
}
dd:nth-of-type(6) {
-ms-grid-column: 2;
-ms-grid-row: 6;
}
dt:nth-of-type(7) {
-ms-grid-column: 1;
-ms-grid-row: 7;
}
dd:nth-of-type(7) {
-ms-grid-column: 2;
-ms-grid-row: 7;
}
dt:nth-of-type(8) {
-ms-grid-column: 1;
-ms-grid-row: 8;
}
dd:nth-of-type(8) {
-ms-grid-column: 2;
-ms-grid-row: 8;
}
dt:nth-of-type(9) {
-ms-grid-column: 1;
-ms-grid-row: 9;
}
dd:nth-of-type(9) {
-ms-grid-column: 2;
-ms-grid-row: 9;
}
dt:nth-of-type(10) {
-ms-grid-column: 1;
-ms-grid-row: 10;
}
dd:nth-of-type(10) {
-ms-grid-column: 2;
-ms-grid-row: 10;
}
dt:nth-of-type(11) {
-ms-grid-column: 1;
-ms-grid-row: 11;
}
dd:nth-of-type(11) {
-ms-grid-column: 2;
-ms-grid-row: 11;
}
dt:nth-of-type(12) {
-ms-grid-column: 1;
-ms-grid-row: 12;
}
dd:nth-of-type(12) {
-ms-grid-column: 2;
-ms-grid-row: 12;
}
dt:nth-of-type(13) {
-ms-grid-column: 1;
-ms-grid-row: 13;
}
dd:nth-of-type(13) {
-ms-grid-column: 2;
-ms-grid-row: 13;
}
dt:nth-of-type(14) {
-ms-grid-column: 1;
-ms-grid-row: 14;
}
dd:nth-of-type(14) {
-ms-grid-column: 2;
-ms-grid-row: 14;
}
dt:nth-of-type(15) {
-ms-grid-column: 1;
-ms-grid-row: 15;
}
dd:nth-of-type(15) {
-ms-grid-column: 2;
-ms-grid-row: 15;
}
dt:nth-of-type(16) {
-ms-grid-column: 1;
-ms-grid-row: 16;
}
dd:nth-of-type(16) {
-ms-grid-column: 2;
-ms-grid-row: 16;
}
dt:nth-of-type(17) {
-ms-grid-column: 1;
-ms-grid-row: 17;
}
dd:nth-of-type(17) {
-ms-grid-column: 2;
-ms-grid-row: 17;
}
dt:nth-of-type(18) {
-ms-grid-column: 1;
-ms-grid-row: 18;
}
dd:nth-of-type(18) {
-ms-grid-column: 2;
-ms-grid-row: 18;
}
dt:nth-of-type(19) {
-ms-grid-column: 1;
-ms-grid-row: 19;
}
dd:nth-of-type(19) {
-ms-grid-column: 2;
-ms-grid-row: 19;
}
dt:nth-of-type(20) {
-ms-grid-column: 1;
-ms-grid-row: 20;
}
dd:nth-of-type(20) {
-ms-grid-column: 2;
-ms-grid-row: 20;
}
dt:nth-of-type(21) {
-ms-grid-column: 1;
-ms-grid-row: 21;
}
dd:nth-of-type(21) {
-ms-grid-column: 2;
-ms-grid-row: 21;
}
dt:nth-of-type(22) {
-ms-grid-column: 1;
-ms-grid-row: 22;
}
dd:nth-of-type(22) {
-ms-grid-column: 2;
-ms-grid-row: 22;
}
dt:nth-of-type(23) {
-ms-grid-column: 1;
-ms-grid-row: 23;
}
dd:nth-of-type(23) {
-ms-grid-column: 2;
-ms-grid-row: 23;
}
dt:nth-of-type(24) {
-ms-grid-column: 1;
-ms-grid-row: 24;
}
dd:nth-of-type(24) {
-ms-grid-column: 2;
-ms-grid-row: 24;
}
dt:nth-of-type(25) {
-ms-grid-column: 1;
-ms-grid-row: 25;
}
dd:nth-of-type(25) {
-ms-grid-column: 2;
-ms-grid-row: 25;
}
dt:nth-of-type(26) {
-ms-grid-column: 1;
-ms-grid-row: 26;
}
dd:nth-of-type(26) {
-ms-grid-column: 2;
-ms-grid-row: 26;
}
dt:nth-of-type(27) {
-ms-grid-column: 1;
-ms-grid-row: 27;
}
dd:nth-of-type(27) {
-ms-grid-column: 2;
-ms-grid-row: 27;
}
dt:nth-of-type(28) {
-ms-grid-column: 1;
-ms-grid-row: 28;
}
dd:nth-of-type(28) {
-ms-grid-column: 2;
-ms-grid-row: 28;
}
dt:nth-of-type(29) {
-ms-grid-column: 1;
-ms-grid-row: 29;
}
dd:nth-of-type(29) {
-ms-grid-column: 2;
-ms-grid-row: 29;
}
dt:nth-of-type(30) {
-ms-grid-column: 1;
-ms-grid-row: 30;
}
dd:nth-of-type(30) {
-ms-grid-column: 2;
-ms-grid-row: 30;
}
dt:nth-of-type(31) {
-ms-grid-column: 1;
-ms-grid-row: 31;
}
dd:nth-of-type(31) {
-ms-grid-column: 2;
-ms-grid-row: 31;
}
dt:nth-of-type(32) {
-ms-grid-column: 1;
-ms-grid-row: 32;
}
dd:nth-of-type(32) {
-ms-grid-column: 2;
-ms-grid-row: 32;
}
dt:nth-of-type(33) {
-ms-grid-column: 1;
-ms-grid-row: 33;
}
dd:nth-of-type(33) {
-ms-grid-column: 2;
-ms-grid-row: 33;
}
dt:nth-of-type(34) {
-ms-grid-column: 1;
-ms-grid-row: 34;
}
dd:nth-of-type(34) {
-ms-grid-column: 2;
-ms-grid-row: 34;
}
dt:nth-of-type(35) {
-ms-grid-column: 1;
-ms-grid-row: 35;
}
dd:nth-of-type(35) {
-ms-grid-column: 2;
-ms-grid-row: 35;
}
dt:nth-of-type(36) {
-ms-grid-column: 1;
-ms-grid-row: 36;
}
dd:nth-of-type(36) {
-ms-grid-column: 2;
-ms-grid-row: 36;
}
dt:nth-of-type(37) {
-ms-grid-column: 1;
-ms-grid-row: 37;
}
dd:nth-of-type(37) {
-ms-grid-column: 2;
-ms-grid-row: 37;
}
dt:nth-of-type(38) {
-ms-grid-column: 1;
-ms-grid-row: 38;
}
dd:nth-of-type(38) {
-ms-grid-column: 2;
-ms-grid-row: 38;
}
dt:nth-of-type(39) {
-ms-grid-column: 1;
-ms-grid-row: 39;
}
dd:nth-of-type(39) {
-ms-grid-column: 2;
-ms-grid-row: 39;
}
dt:nth-of-type(40) {
-ms-grid-column: 1;
-ms-grid-row: 40;
}
dd:nth-of-type(40) {
-ms-grid-column: 2;
-ms-grid-row: 40;
}
dt:nth-of-type(41) {
-ms-grid-column: 1;
-ms-grid-row: 41;
}
dd:nth-of-type(41) {
-ms-grid-column: 2;
-ms-grid-row: 41;
}
dt:nth-of-type(42) {
-ms-grid-column: 1;
-ms-grid-row: 42;
}
dd:nth-of-type(42) {
-ms-grid-column: 2;
-ms-grid-row: 42;
}
dt:nth-of-type(43) {
-ms-grid-column: 1;
-ms-grid-row: 43;
}
dd:nth-of-type(43) {
-ms-grid-column: 2;
-ms-grid-row: 43;
}
dt:nth-of-type(44) {
-ms-grid-column: 1;
-ms-grid-row: 44;
}
dd:nth-of-type(44) {
-ms-grid-column: 2;
-ms-grid-row: 44;
}
dt:nth-of-type(45) {
-ms-grid-column: 1;
-ms-grid-row: 45;
}
dd:nth-of-type(45) {
-ms-grid-column: 2;
-ms-grid-row: 45;
}
dt:nth-of-type(46) {
-ms-grid-column: 1;
-ms-grid-row: 46;
}
dd:nth-of-type(46) {
-ms-grid-column: 2;
-ms-grid-row: 46;
}
dt:nth-of-type(47) {
-ms-grid-column: 1;
-ms-grid-row: 47;
}
dd:nth-of-type(47) {
-ms-grid-column: 2;
-ms-grid-row: 47;
}
dt:nth-of-type(48) {
-ms-grid-column: 1;
-ms-grid-row: 48;
}
dd:nth-of-type(48) {
-ms-grid-column: 2;
-ms-grid-row: 48;
}
dt:nth-of-type(49) {
-ms-grid-column: 1;
-ms-grid-row: 49;
}
dd:nth-of-type(49) {
-ms-grid-column: 2;
-ms-grid-row: 49;
}
dt:nth-of-type(50) {
-ms-grid-column: 1;
-ms-grid-row: 50;
}
dd:nth-of-type(50) {
-ms-grid-column: 2;
-ms-grid-row: 50;
}
You can use: https://www.sassmeister.com/ to generate the CSS (so you don't have to install gulp/grunt or use a local preprocessor).