Also having this issue, tried the dying 3-5 times thing, also didn't work, any ideas?
Viewing post in Baldi's Basics The Ultra Decompile comments
Ok, so I have a semi-fix.
If you press F8 while in the school, you get the debug console window. In this window, you can type "scene load School_2", this will load the "grand opening" version of the school.
You can also view other scenes to load with "scene list", although using "scene load School" will send you back to Null style.
It's not a permanent fix, as you'll have to do this each time you play, but it's something.