We left the park late and the monorail was still running.
I had to do the same thing I watched all the fireworks close to the entrance gate then had to take a bus to the monorail then to Epcot to catch my shuttle to the Renaissance.I was worried but had time to do it .
I think it runs up until an hour after the park closes. I'm not exactly sure but I think it does.
Thanks! Your answer is awaiting moderation.