The footprint on the bathmat is not from someone having blood on their shoe. It was a bare foot footprint. So the blood could have been on the pants leg but not the shoe at that time. If Rudy put his shoe back on before going back to Meredith's room there would still be no bloody footprints (from someone wearing shoes) in the hallway.
MOO
Oh yesss, I forgot that part of the story - so he's in the bathroom, he takes his shoe(s?) off to rinse his pant leg, then he places his foot on the bathmat, the water drips down and creates a bloody stain, then he puts his shoe back on, then he walks back to the bedroom to take the towels, leaving no prints because of his blood-less shoes, then he steps in blood in the bedroom, then he walks out and leaves bloody footprints.
Do the supporters of her innocence really believe this is at all probable or even possible?
IMO, it is very, extremely far-fetched.