Hello and Welcome!
One way of sending audio from ableton to jammer is to use a program called loopback. It basically allows to you to route audio from different applications on your computer. I believe it is Mac only and it also has a price tag. I currently use this to route audio from GarageBand to jammr.
Here is the link:
https://rogueamoeba.com/loopback/Look forward to playing with you!