Just wanted to chime in that the Slot thing worked for me.
In my case, I was trying to use existing animations from a UE Marketplace asset I bought (ladder animations), and it had its own slot made for it (they used a default slot for just the climbing, and a separate one for getting on/off the ladder).
I created a slot with the same name as what the ending animation (climbing off the ladder), plugged that into my character’s AnimGraph and it worked!
Maybe another way to go about it is to make a slot just for your animation. Did not test that but maybe worth a try?