Installed Collabora - loads document but can not edit document

I have installed Nextcloud on a server hosted by a web hosting company.
I can not run Docker with my web hosting company.
I have installed Collabora on a VM I run on my server at home.

I installed according to the guide and my documents load but I can not edit the documents.

I have a working SSL Certificate on each server.

My home server can not be connected on either port 80 or 443 (ADSL ISP restricts those ports)

My Collabora server is using port 4433 for https connection.

Does anyone have any input on what might be wrong?