Not sure how heavy that butt is but hopefully it will be ready by dinner time. Good thing is that you are slicing so 195F vs 205F will cut about an hour and a half or so off the total time is my guess.
Pork butts and briskets get to 150F deceivingly fast then you spend hours and hours getting to 180F. The rest of the way is not as slow but also not fast itself.
Don't be afraid to crank the oven up to 375F with the pork butt uncovered, at the end you could even do 400F but I wouldn't go there too long unless you decide to wrap it. At or over 400F you can start to get some over-crisping going.
You gave it a shot and learned a thing or 2 for the next attempt. It happens to us all from time to time.