Moving actors through different levels

Hi everyone, I am working on a turn-based multiplayer game in which the player creates a warband of 7 units, customizes it and then uses it in matches against other players.

I am having problems moving the actors created during the warband creation phase into the match level as a result of matchmaking: i managed to add them to the actors-to-keep list with GetSeamlessTravelActorList() in the starting level’s player controller, but they never reach the destination.
I checked if they are correctly stored when the transition map is reached overriding GetSeamlessTravelActorList() and printing the length of the actor list both when bToEntry is true and false and i saw that they are lost during the first transition (ie from the starting map to the transition map). Also, clients never get to call GetSeamlessTravelActorList() and are not moved with the server, even though I am 100% sure they are sharing the session, because I put several checks to make sure that matchmaking is working and sessions are properly created and joined; so only the server is moved.

Is there anyone that could help me understand why it’s not working as intended?

As far as regards the settings: i made sure i checked bUseSeamlessTravel in both starting and destination game modes and i set the transition map in project settings.

Here’s the code i put in GetSeamlessTravelActorList() override:

And here are the blueprint nodes for the session creation: