Problem Setting two PHP version on XAMPP on Windows

Question

I am running a XAMPP installation with PHP 5.6 for compatibility reason with my existing projects, but my new project requires PHP 7+.
I'm trying to install PHP 7.4 alongside my existing PHP 5.6 following the guide in this question, but I only end up in a 404 page for that project.
My httpd-xampp.conf looks like this

#
# XAMPP settings
#

<IfModule env_module>
    SetEnv MIBDIRS "C:/xampp/php/extras/mibs"
    SetEnv MYSQL_HOME "\\xampp\\mysql\\bin"
    SetEnv OPENSSL_CONF "C:/xampp/apache/bin/openssl.cnf"
    SetEnv PHP_PEAR_SYSCONF_DIR "\\xampp\\php"
    SetEnv PHPRC "\\xampp\\php"
    SetEnv TMP "\\xampp\\tmp"
</IfModule>

#
# PHP-Module setup
#
LoadFile "C:/xampp/php/php5ts.dll"
LoadFile "C:/xampp/php/libpq.dll"
LoadModule php5_module "C:/xampp/php/php5apache2_4.dll"

<FilesMatch "\.php$">
    SetHandler application/x-httpd-php
</FilesMatch>
<FilesMatch "\.phps$">
    SetHandler application/x-httpd-php-source
</FilesMatch>

#
# PHP-CGI setup
#
#<FilesMatch "\.php$">
#    SetHandler application/x-httpd-php-cgi
#</FilesMatch>
#<IfModule actions_module>
#    Action application/x-httpd-php-cgi "/php-cgi/php-cgi.exe"
#</IfModule>


<IfModule php5_module>
    PHPINIDir "C:/xampp/php"
</IfModule>

<IfModule mime_module>
    AddType text/html .php .phps
</IfModule>

ScriptAlias /php-cgi/ "C:/xampp/php/"
<Directory "C:/xampp/php">
    AllowOverride None
    Options None
    Require all denied
    <Files "php-cgi.exe">
          Require all granted
    </Files>
</Directory>

<Directory "C:/xampp/cgi-bin">
    <FilesMatch "\.php$">
        SetHandler cgi-script
    </FilesMatch>
    <FilesMatch "\.phps$">
        SetHandler None
    </FilesMatch>
</Directory>

<Directory "C:/xampp/htdocs/xampp">
    <IfModule php5_module>
        <Files "status.php">
            php_admin_flag safe_mode off
        </Files>
    </IfModule>
    AllowOverride AuthConfig
</Directory>

<IfModule alias_module>
    Alias /security "C:/xampp/security/htdocs/"
    <Directory "C:/xampp/security/htdocs">
        <IfModule php5_module>
            <Files "xamppsecurity.php">
                php_admin_flag safe_mode off
            </Files>
        </IfModule>
        AllowOverride AuthConfig
        Require all granted
   </Directory>

    Alias /licenses "C:/xampp/licenses/"
    <Directory "C:/xampp/licenses">
        Options +Indexes
        <IfModule autoindex_color_module>
            DirectoryIndexTextColor  "#000000"
            DirectoryIndexBGColor "#f8e8a0"
            DirectoryIndexLinkColor "#bb3902"
            DirectoryIndexVLinkColor "#bb3902"
            DirectoryIndexALinkColor "#bb3902"
        </IfModule>
        Require all granted
   </Directory>

    Alias /phpmyadmin "C:/xampp/phpMyAdmin/"
    <Directory "C:/xampp/phpMyAdmin">
        AllowOverride AuthConfig
        Require all granted
    </Directory>

    Alias /webalizer "C:/xampp/webalizer/"
    <Directory "C:/xampp/webalizer">
        <IfModule php5_module>
            <Files "webalizer.php">
                php_admin_flag safe_mode off
            </Files>
        </IfModule>
        AllowOverride AuthConfig
        Require all granted
    </Directory>
</IfModule>

#
# New XAMPP security concept
#
<LocationMatch "^/(?i:(?:xampp|security|licenses|phpmyadmin|webalizer|server-status|server-info))">
        Require local
    ErrorDocument 403 /error/XAMPP_FORBIDDEN.html.var
</LocationMatch>

# Begin multi-php modifications
Listen 8081

ScriptAlias /php-cgi/ "C:/xampp/php7/"
<Directory "C:/xampp/php7">
    AllowOverride None
    Options None
    Require all denied
    <Files "php-cgi.exe">
          Require all granted
    </Files>
</Directory>

<VirtualHost *:8081 "C:/xampp/Telegram"> <--originally was C:/xampp/htdocs/Telegram
#    UnsetEnv PHPRC                      <-- Tried to enable/disable this and the above settings, unsuccessfully
    <FilesMatch "\.php$">
        SetHandler application/x-httpd-php74-cgi
    </FilesMatch>
</VirtualHost>

#End multi-php modifications

I feel there's something in the default settings forcing xampp to run PHP 5.6 and only scripts from the ./htdocs directory, but since I'm quite noob about xampp configuration, I'm asking here what to do.
HERE the result from Postman, trying to connect to the project.

P.S. without the multi-PHP modifications the page loads "correctly" (considering the PHP 7 requisite)