Since you left the window open a night and day, I am sure the bat left. Most likely it will not be back, since it had an unpleasant experience in the house. Probably a youngster that did not know any better. It is that time of year, you know.

Bats are quite small, so I would not guarantee you noticing any rotten odor if it died. Especially if there are ants, which are pretty good at cleaning up small carcases.

There was a bat that flew in and went straight to my sons bedroom. My son wasn't in there at the time the bat flew in. We closed off the room and called my dad for help cuz it was late at night and wild life patrol wasn't open. Anyways when my dad got there the bat disappeared. Animal patrol told me to open the window so I left it open all day Amd night and some of the day and night the following day. I'm hoping the bat figured it out and flew out. Days later my mom and I sanitized the whole room Amd closet And didn't see any signs of the bat. My son hasn't been in his room at night since the day before it happened cuz he was scared. And only started going in his room during the day about 2 weeks ago (4 weeks after the bat came in). It's been 6 weeks and he decided to sleep in his room tonight. Is it safe to let him sleep in there? He's not scared anymore but I am lol :( I'm worried cuz they can carry rabies. Just a paranoid mom here.