Thanks for the model! I've always avoided shell models because it has never made 100% sense to me, but im starting to understand it more given that my model has been converted. Thanks! Funnily enough, when I released all rotations, I did not receive a fatal error and instead, it seems to have generated identical results. This is very close to what I am looking for, but unfortunately still not completely representative. To repeat what I said in my reply to Shaun, A similar beam connection, where all rotation at both ends is released, but where the beam itself remains parallel to the global vertical axis would be an exact representation of AutoPIPE (which I am starting to realise is way oversimplified if Creo can't even simplify a connection enough to match it).
I did some additional exploring down this path, and it is starting to look impossible, at least with this solution.
EDIT:
As per my reply to Shaun, I modified your solution and the AutoPIPE model to a point where I think they coincide. Thanks for your help!