The hush-hush characterization is totally normal. It's a mil payload and they are not going to tell you any more than necessary.

Yesterday's NROL-111 launch from Wallops is the more top secret operational sat.

In contrast to NROL-111, Space Force did talk quite a bit of non-specifics on TacRL-2. The spaceflightnow articles by Stephen Clark are good. Also see:

https://space.skyrocket.de/doc_sdat/odyssey_tacrl-2.htm

Orbit is 405 x 452 km x 97.5 deg sun-synch (from nasaspaceflight forum). So it's for surveillance. Assuming they are not flat-out lying, then they are most likely testing sensors and stuff. Like what X-37 does. Except the military also want to keep Pegasus operational.