They are working on Live and Offline traffic in SU15 so you don’t have too long to wait.
Currently on SU15 Beta 1.37.8.0. Scheduled SU15 release is 26th of this month but might slip.
Won’t necessarily fix all current release issues but when I’ve seen a/c stuck taxiing they eventually disappear. Not ideal but better than having them stuck indefinitely.
The only time I’ve seen Live Traffic sharing a gate is when I’ve had Ground or Static a/c on at the same time.