Yes, very odd. I am thinking why would they need to have cleaned the kitchen anyway? They must have been cleaning off RS prints in the kitchen, because Rudy prints they wouldn't care about and Amanda prints would have excuse for being in the kitchen. The only one who wouldn't belong was RS. But they could have said RS's were from the day before when they were eating lunch there. So IMO, it was because Rudy's prints were intertwined in the same area with RS prints (kitchen), that's why they cleaned off kitchen surfaces. And even though Amanda lived there, of course she would not want her prints intertwined in same area along with Rudy, either. That would also be the reason they cleaned off the large bathroom - of course fingerprints are not like the footprints, they cannot distinguish who's is who, so they had to clean off all the prints, otherwise their prints would show up alongside/intertwined/same area as Rudy's.
My understanding has been that fingerprints are most often not visible to the eye; surfaces are dusted for prints, to reveal the prints. Why would they not eliminate fingerprints from Meredith's room?