Yes, agree at least 2 issues as indicated in the OP.

Yes, there is power to the ammeter. That was confirmed. Given there is power to all other lights, methinks power should be going through to the light switch fuse and wiring, which it is not. Also as reported in the OP.

The only signal not working is the LF, but the emergency flasher does work, as do all the others.

So, there in is one “Gremlin”.