His gpa is basically set now. Even if he does 30 credits this year, and gets a 4.0 in all 30 credits, his GPA would rise to a 3.36. This is assuming he gets a 4.0 in all 30 credits. His double major in chemical engineering and philosophy have set his gpa in stone basically.
This thread is pretty spent. The OP has a perspective/plan that is set in stone even if there are rationale alternative options. The OP's question has been answered (looks like the general consensus is, if you are really going to choose between just SGU and BGU, go with BGU).
I hope the OP's nephew is able to achieve his goals and wish him the best; I think the general consensus is that taking a year and trying again for a US MD school would be a good use of time and that he is unnecessarily setting himself up for an uphill battle when it comes to residency with this plan to attend BGU but that is the OP's nephew's choice as a sentient adult.
For what it's worth, I had a GPA similar to the nephew's (albeit in biochemistry/molecular bio not chem-E) though with a borderline MCAT on my first application cycle and I was waitlisted at my state school (the only school I applied to). I retook the MCAT and some graduate level courses (while working my full-time job... I took a total of 3 years off between undergrad and medical school) and reapplied to more schools and was accepted at my state school. What people are suggesting here is NOT unheard of; in fact, if the situation was hopeless, many of those contributing here would say so... SDN posters do not typically pull punches when letting someone know if they think they are beating their heads against a brick wall to no purpose. So, at least I think I am proof that the nephew could feasibly try again next year with a reasonably good shot at a good result. But of course my case was way back in ye olde 2005-2006 and things just continue to get more competitive.
I would also like to add that I wish the nephew could step back and reevaluate his idea that any more time is "wasted" and that taking this step now is "getting on with his life." I will say pointedly that I have many colleagues who took a variety of paths to medical school; some went straight through undergrad and med school with no time off and some like me had some gap years. I will say some of those that went straight through were fine with it and had no regrets and some later said they wished they'd taken a year or two off. However, I have
never met anyone in medical school or residency that regretted taking "time off" between undergrad and med school. The nephew can do so many things in that year in addition to improving his application, and medical schools do not look down on this sort of thing.
Finally,someone involved in the GME administration at my training site told us today that THIS is the year where the number of US medical students in the match is expected to exceed the number of available residency spots. This has been expected for awhile given that the the number of students increased a few years ago with new schools opening and existing schools adding extra spots (my own alma mater increased class size by 10 spots/year beginning with my class) while residency spots have been frozen since 1996. There are more people seeking residency positions than ever and this problem is only going to get worse over the next few years. This is not to say that the nephew absolutely won't match as an IMG (no one can predict success or failure with absolute certainty), just that statistics are already against him if he pursues his current plan and will not improve but worsen in the near future.
So best of luck to the OP's nephew. After spending so much time and effort to get into medical school, most here can not fathom choosing a path that doesn't offer the best chance at matching into a residency of choice when a better alternative probably still exists, but every person has their own motivations, etc. If I were the OP I would take the extra year, but I am not. I hope he does not look back on this decision with regret but it is difficult for me to imagine a scenario where he will not.