SAML Team Chat Channel Assignments

We want to be able to have automatic channel assignments using info from a user's SAML SSO sign in.

I have created department Channels and am using SAML for assigning the user to that already.

I recently found out that you can't have more than 1 SAML assignment.

Meaning if you do a departmental SAML mapping to a Channel, you can't have a different row for their location and also map to a location-based Channel.

I tried using Group memberships as well and it seems like there is a limitation with that logic too.

So what do people do in this case?
I want to have a user automatically get put in a departmental channel AND a location-based channel.