I don't know the specs on those pumps, but I doubt that any of them could provide enough pressure for that type of application. If I were you, I would clean the kegs outside. You don't need a lot of pressure really. Mostly you want to be able to rinse well. I would find a way to get water outside through a window or something. A garden hose adapter on a sink faucet is a good idea or tap into the line under the sink. Be careful with the keg in a bathtub. I could see it damaging the tub if it's porcelain or anything similar. I'd put a rubber mat in the tub to protect it if you must use the tub. It can be a major challenge to brew in an apartment situation. Oh yeah, have you looked to see if the building has any outside faucets? That would be my first option even if you have to bribe the maintenance guy. Ply him with some home brew if necessary.