Collabora Fileserver tries to open broken paths

Hey Humans, i have tried many many many many different Nextcloud/ Collabora combinations, at least i iterated through Collabora versions quite well. The Install Script and stuff where helpfull, and i can’t use a Docker Image, my Provider doesn’t allow me to do that, so i used the Script on my Ubuntu 16.04 64 bit Server with Nextcloud on the same machine, Apache, Letsencrpyt etc. the furthest i got was with Collabora 2.0 and Nextcloud 12.0, i’m now down the Rabit Hole for 2 Weeks working almost daily 4-8 hours to get any such combination to work.
Did anybody ever face a message like this? :

wsd-00424-0481 23:25:32.460201 [ client_req_hdl ] TRC  Fileserver request: /loleaflet/dist/admin/l10n/ui-de.json
wsd-00424-0481 23:25:32.460319 [ client_req_hdl ] ERR  FileServerRequestHandler: File not found: /opt/online//loleaflet/dist/admin/l10n/ui-de.json

It opens the admin html but when i try to open a file, i get an empty frame and those errors, should i rewrite the Fileserver? i guess it’s an easy hack compared to other options right?