You can fit a pack n play with the second bed pulled down, but IMO it is tight - especially if you have a large open stroller, etc. If you plan so you have everything you need for that next day in a single bag that might help make it easier so you’re not trying to open a lot of bags for a single morning.
I am all about saving money, so for a single night I think I personally would do it... but go into it realizing it’s going to be tight, there won’t be much room to just be walking around, but it’s only one night and sounds like you’ll only be using the space to sleep.