I have bathed one child in my time doing this. He decided to smear poop all over him and his playpen during quiet time. I went to get him up first and found it, so I was able to bath him quickly while the others were safe in playpens.

However, under normal circumstances, no, I can't watch children and bath another at one time. I don't even go to my upper level while I have kids. As a result my downstairs is always clean and my bedrooms always a mess. LOL

In this situation I would have wiped and used a damp cloth best I could, if he needed further care I would have called the parents.