Okay I have to ask because I’m not a marble expert. Does urine really harm marble that badly?
I don’t know, but it seems to me that any surface that can be so easily ruined by stray drops and splashes is a lousy material to use in a bathroom.
It can etch it, and cause a yellow tinge to remain - the main thing is the gloss difference. Acids and sanding will fix it if nothing else, but proactive maintenance with a good terrazzo sealer (which will seal the grout too) makes marble pretty impermeable.
Acids will etch marble by dissolving the calcium. Piss contains acids. The solution is to dilute the droplets with water by routine washing the piss off the floor. The landlord should have a requirement in the lease to clean the bathroom floors of piss.