Opens fine for me. Hole and slot are both there. Seems like maybe a graphics specific issue on your computer (like @dgschaefer said.)
What build of Creo 4 are you running?
Look for the config option "enable_absolute_accuracy" and set it to yes. That should let you use absolute accuracy. I've been using Creo / Proe for over 20 years and have always used absolute accuracy and recommend it as the default. I'd try it, it still might do the trick but it seems unlikely based on the other things you've tried.
I opened your file and saw the same thing as you on my computer. I changed to absolute accuracy (0.0001) and the problem went away.
Creo4 m060 was the last released in early August.
Creo 22.214.171.124 was released in early July.
Hopefully it will be fixed in Creo 126.96.36.199 scheduled for early October.