If theres a wall/door/gate etc between you and the bank it wont bank. It uses breshnam path iirc
I was doing it at the cows north of lumbridge (the gate was open) I figured it would use draynor, I also just ran it at the east lumbridge goblins and cows for 30 mins with combat disabled and it just got a full inventory and kept walking around. This time I made it bury bones just in case they were the problem (I want it to bank literally everything sellable). It just doesn't know what to do when it's full, I can't find any missing settings or anything, hmm
edit: ok more weird results, I ran it at goblins with a full inventory, no combat and made it only loot 1k items, it walks around doing nothing. For a while I think runemate was lagging (this bot causes a lot of lag for me, by that I mean cpu). Every 2 mins or so it walks across the lumbridge bridge and sits there for 30 seconds, the mouse like hovers on the map where it needs to walk next, and then it just goes back to goblins and walks around.
edit2: this is in OSRS btw