Ok I’m giving parent to parent advice here, as a mom of a candidate to USNA and applicant of the 4-year NROTC scholarship. And having a front row seat to his efforts and what’s he’s learned over more than a year at this point.
First, my son wants to serve as an officer in the Navy. That is first second and third on his list. It took our family a little bit to get that because we were focused on this aspect of college academics or that aspect of career path. We really didn’t “get it” right away but he did. Crystal clear: he wants to serve. That is the driver here. And his perspective is sure I’m interested in X career but the Navy will probably also have a say in where I’m most useful career wise!

So because it sounds more like your son has a very specific career in mind, I think it’s well worth exploring (quickly) how likely it is he could pursue that. I don’t know. It sounds amazing but it doesn’t really jive with all I’ve learned from my son about how this works — sure you can pick a major, but a career? Maybe maybe not.
Second, as I understand it, you can major in underwater basketweaving and you’re still taking a million very advanced STEM courses, whether in NROTC or at USNA. So just confirm that the lack of interest in STEM majors isn’t a lack of interest in STEM.
Along those lines, your question is if it’s better to pick a tier 2 major with a Chinese minor vs a Tier 3 (Chinese) major. I certainly can’t answer that but there are some facts at play. Tier 3 majors are capped at 15% of scholarships. So the math on going tier 3 isn’t good. BUT… again from what I understand that does not mean you just pick some tier 1 or tier 2 major to make your application look good. His application should reflect what he wants to do; I don’t think anyone would recommend trying to do otherwise. Clearly there is a need for some tier 3 majors or they wouldn’t have them. Maybe he’s a brilliant linguist with fluency in Mandarin. Maybe that is useful to the Navy. But whether they will see your son as having the potential for that isn’t something anyone knows. But if that’s his passion and goal, starting to mess around with throwing things in the application that aren’t really aligned with his interests isn’t something I’d recommend doing. He has to do that discernment and make that decision.
Finally, like all moms, I think my son is pretty amazing.

He is a top student in a very tough district, with strong SAT scores, and has done a lot with leadership and service. He just got a senatorial nomination to USNA in a competitive state. And he STILL thinks his chances at both USNA and the NROTC scholarship require daily prayer! (I’m dead serious.) And he knows the men and women who are aiming for this are great and equally deserving. My point is he doesn’t think he’s a shoe in, doesn’t talk about it like that at all, in fact quite the opposite — since his apps are done he is working hard on plan C (college programming) and D (our state school’s honors program / engineering program). Why do I mention this? Well you said you need USNA or the NROTC scholarship to afford college. And that is very common and understandable these days. But these are highly *highly* competitive! So I would say, time to also develop a very good plan C or even D. Maybe a community college has a 2+2 program, maybe it’s a financial aid package (get that FAFSA in!), scholarship applications, work study, etc. Regional universities are wonderful places that typically cost less than even state schools. I guess I’m just saying, this is a terrible bet for affording college that only a few of a large number of probably very deserving men and women benefit from. Have a backup plan! Or two!
And one final piece of advice. There are a lot of components of the NROTC application that are out of your son’s direct control to get in. “Trust but verify” that they are all sent, complete, AND received by his recruiter before the deadline. My son had to do a whole lot more proactive tracking and emailing and pushing than I ever would have imagined. It’s all good experience but… wow. It takes a lot longer for guidance and teachers to send things in than you might think in some cases. And people are human and make mistakes. Plus it’s peak application time and flu season etc etc. So tell him to get it done ASAP!