Yes, It is possible to read an odt file from byte Array and then load it in webodf editor.
To do so ,you will have to use javascript blob objects to construct a file from a byte array(desired file in bytes format).
Then you can get a temporary url for that blob object which is very similar to a file itself.The 'url' is temporary url created and stored in browser.
Once you have the url for your file ( bytes => blob => getUrl ) then you can easily load the file in your webodf editor using 'openDocumentFromUrl' function.
var file = new Blob([data], {type: mimeType});
// data => your bytes file
// mimeType => the mimetype of file(odt : application/vnd.oasis.opendocument.text)
var myUrl= URL.createObjectURL(file);
// get the temorary url from blob object.
editor.openDocumentFromUrl(myUrl, function(){});
// editor is the active webodf context object which you get when webodf context is created