My son just went through US to GE transition last semester. I usually won’t recommend this route to other students because it was stressful enough for my son to worry about survival of his first semester in college and add another stress for get himself into GE at the same time. However, looking at your son’s academic HS record, if he can get CHEM 1035 & 1045 credits from his HS, I think risk of him falling below 3.0 is minimal. Last semester, students from this CHEM class were splited between one who passed with C or D vs failed with F or withdraw. This were shocking to kids both from GE and US who never got anything below B in their life.