Same issue. Since Larian won't let the hirelings be fully customizable I made a 4 person multiplayer game. Got to lvl 3 and one just stopped following while chained. It happened after I boxed them to switch to Karlach to for her upgrade. So I led with the one that won't follow. Despite not being the charisma character. I have boxed and unboxed them all many times. Hit lvl 4 boxed another one to switch in Shadowheart. Switched back and now that one also won't follow anyone. I completed the game previously with no multiplayer and never had an issue.
A side note the pop up cutscenes that trigger. Sometimes target characters not leading nor under my control.
Some simple fixes. Make the hirelings fully customizable name race the whole nine yards. Allow players to change in different characters to speak during cutscenes instead of some flawed first come first serve targeting system.
