Plugins and JS files

Dear,
we are using Canvas HTML theme to create new website with booking engine, but engine is provided through iframe and hosted on different server, so we need to supply those pages with our own header and footer files, but cannot use html, meta, head and body tags, so I can't disable preloader? Also, all scripts and fonts need to be loaded through URL and we are unable to load some JS functions and header and footer is loaded, but not showing...
Can you please analyze these two urls and advise us what to do? I am not sure which plugins and other don't need to load, and does it need some more linking through JS files, all are loaded via absolute paths eg https://allegrakrstanja.com/ch/js/function.js

https://allegrakrstarenja.com/ch/index.html
https://booking.allegrakrstarenja.com/start?aid=204028

Any help will be much appreciated :)

jQuery v3.1.1 is preloaded by their side

I found solution, as code is well formated, all you need is to exclude plugins from plugins.js that makes problems...

Also, you need to change $window.load() to $window.on('load', ())

Solved