I just came across this situation, believing it's a bug.
Initially, I have 1 SSID (A) that uses internal AD NPS server as RADIUS (A) and everything worked fine until another SSID (B) with a cloud RADIUS (B) is introduced.
Seems like the authentication of SSID (A) is not passing to RADIUS (A) at all. No request is received at the NPS server and the authentication timed out.
SSID (B) with RADIUS (B) works fine though. So do the other SSIDs that have PSK. Tested at 2 separate sites and got same result.