So, most of the time heist that we see in endgame was supposed to happen, right? but not Loki's escape. so, in the actual sacred timeline, the avengers would have gotten the tesseract and left. however, they were forced to go to camp Lehigh. so the Lehigh heist would not be part of the sacred timeline. but it must not have deviated enough to be pruned. because iron man later died, his conversation with his dad must not have caused any branches in the present. and this must mean that cap would have gone and lived with Peggy even if he never saw her at camp Lehigh. otherwise him getting old would have caused the timeline to branch and consequently get pruned.