A global way of searching is not possible because it took way too long in our tests.
You could create a report which checks for all computers which have egui.exe found (no matter which location)
This would show you all pc's with the software installed
Also If I compare my scan report to the software report for this file/product I seem to be off, shouldnt they be pretty much equal
It depends on your waittime for each item, maybe you scan software every 30 days and files every 1 day.