Generate Simulation Setup Script Fails

Ok, got it to work. Added C:\altera_pro\26.1\qsys\bin to the path, opened a Windows command prompt, cd to the project directory, then ran the ip-setup-simulation.exe command with the same parameters when run by the GUI and it works (I still have to click yes on the User Account Control dialog). I don't know why it stopped working with the GUI Tools>Generate Simulation Setup Script for IP... command, but this is the workaround I used.

[Update] The ultimate fix was to change the Quartus shortcut to run as admin. That way, when the tools>generate simulation setup command is run, it is also elevated to admin and can run. Not sure why that command alone started requiring elevated privileges to run.