Giving a solution on the problem if someone ever comes up with something similar.
On ideal scenarios page load speed, DOM elements, js files etc run optimal or are precached so the scroll will occur as intended. On the other hand it looks like in a real scenario the images I have placed create the scrolling height and all the elements must be already loaded to calculate everything correctly. Therefore I used imagesloaded.js where I run the scrolltriggers AFTER the images on the section are loaded and everything works like a charm.
Hopefully it can be a solution to someone else too out there.
Once again, thanks @Rodrigo for the time spent looking into it and this amazing community / forum!
Nick.Ls's post in ScrollSmoother breaks Scrolltriggers was marked as the answer