Nextcloud client rework help

Hello there,

I’m tasked with using the nextcloud client to sync with an apache webdav based storage. My constraints are that i cant use the nextcloud server because of the limited resources on the server and the amount of rework that would need to be done on the storage structure. I’m aware of the external storage linking app within nextcloud but that is not what we are looking for. I came across this thread they got it working with group office and internally nextcloud uses sabre-dav as well, so basically they didnt have to touch the client source.
What I wanna know is where do I get started if I wanna rework the client source to completely skip the /remote.php/webdav and directly start propfinding webdav directories?

Any help would appreciated.