Developer-Dude If I really wanted to go through the effort, would it work to compile and build GrapheneOS to run on this phone?
A big step is missing. It would be necessary to port GrapheneOS to the device. Device drivers and other frameworks would need to be adapted, and features that can't work (duress PIN) would need to be removed.
Depending on your prior experience it might take from one month to 11 years.
And, my honest opinion, that amount of effort might arguably be better spent developing some useful app for GrapheneOS. I think I hear lots of complaints about SIP clients.