Just talked to a friendly bloke at the WD support at Netherlands. He took my logs to escalate the case and get back to me.
As for the co-browse: if you happen to talk to WD support (chat/phone) the session number is requested to establish a remote access session…
Friendly advice to all: if you do have a problem, open an issue for it (not forum thread) and if noone replies, call WD on the phone! I can’t stress the last part strong enough.
Cloud OS 5 is still a joke regarding its quality, but at least now I feel a bit better for having a possible solution coming by!