Meta tags implementation on MeteorJS - meteor

Question

I am maintaining a MeteorJS web app and I need to add some specific meta tags into homepage.
I see that there is a head.html in the project that has all information, including
the existing og meta tags, I tried to add the specific meta tag there and restarted the server.
If I right click view source on the homepage, I can see the newly added meta tag.
However, if I try to use Facebook debugger to see what the FB Crawler sees, the newly added meta tag is not seen by the bot. In fact the bot sees some additional twitter meta tags that does not exist anywhere in the project.
Investigating further, I noticed the project uses a library called
manuelschoebel:ms-seo: https://github.com/DerMambo/ms-seo
This library is initialised in the Meteor.startup like this:
Meteor.startup(function() {
if(Meteor.isServer){
if(Meteor.DEBUG){
robots.addLine('Disallow: /');
}
robots.addLine('Disallow: /admin');
}
if(Meteor.isClient){
// default SEO
return SEO.config({
title: '...',
meta: {
"description": "..."
},
og: {
'image': '....'
}
});
}
Now I am guessing this SEO library is the reason why the bot does not see the newly added meta tag in the head.html.
What is the right way to add the newly meta tag in a clean way? why is this SEO library not respecting the head.html in the project?