Here is some additional information:

CAS-4B: https://network.satnogs.org/observations/1469843/

Here you can see two SSTV transmissions starting at about 150s. I see no impact on the ongoing qso's going on higher up the passband.

CAS-4A: https://network.satnogs.org/observations/1469844/

Here there is an SSTV transmission at about 200s, also doesn't seem to impact the ongoing qsos.

And yes - all of this was in SSB. I suppose a trial in NFM would really cause havoc on the transponder.

--Roy K3RLD