Unpadded stand
 

What would you do if the referee stand at the match is not padded, and the coach/AD says there's nothing they can do about it?

Would you officiate the match from the floor?

I have. And, let the assigner or state association know (depending on the practice in your area).

That’s what my HS unit asks us to do.
Don’t remember if the local college board addressed it as explicitly.

NCAAW:

1.5.4 Referee Stand
A referee stand is required� (See Rule 19�2�1�)

FED: casebook, D: PreMatch Responsibilities, The First Referee Shall: (page 66 in last years book):
If the platform is not stable the referee may officiate from the floor

(I'd extend that the te padding issue).