Required Apps assigned to dynamic group are being skipped during pre-provisioning?

After a long set of back and forths MS support (long story), I had to remove a requirement script that I set on my applications and app tracking went back to normal.

For some reason, the script doesn't evaluate consistently. It will sometimes mark as "false" and then shortly after that evaluate as "true." 

• When it evaluates as false, it will "skip" the app and continue with the others. The ones that evaluate properly are tracked.
• Shortly after the app is skipped, it evaluates as true later in ESP and will install silently.

All the script does is check the explorer process and see if it's running under with an account that matches "defaultuser." If it matches, the bool is true, else false. If true, the app will install. It ensures the apps only install during ESP. I don't believe it's an issue with my script because 

• it was consistent prior to me making this post
• it evaluates as true when I run it manually during ESP, both with the defaultuser0 account and under the system account with psexec

MS believes it's my script but that this point, the ticket was open since April, apps are being tracked properly and I don't wanna fight anymore