Hi Brian. You're finding your way around ScubaBoard pretty well already!
As for your questions, I've answered some via PM, but you didn't mention the disabled war vets aspect (unless I read it all too fast), so I'll address that bit here after summarizing what I've already expressed privately.
In general, I don't think the all-inclusive programs that some Thailand shops offer are great for everybody. Students get locked in to a place and shop by virtue of having paid a big up-front fee that generally includes things you, Brian, may not want. For example, many of those programs include a set of "free" gear, but if you've got your own, the discount is minimal, and if you don't, the gear is quite basic, and upgrading will add to the price tag. Many include housing, but you might not like the housing or your roommates, and of course to get out of that into alternative housing adds to the price tag. What I'm saying is that I prefer, in my own training of DMs and interns, to follow a pay-as-you go approach. Then if the student thinks s/he needs something different from what I'm able to offer, s/he's not locked in, unhappy, and regretful.
If what I do is in line with the student's objectives, then all is sweetness and light! If a student needs gear, we find what fits his/her budget and preferences; if a student wants housing, we find what works best according to his/her wishes. I don't do any one-size-fits all training; everything is individualized. OTOH, some people find the planning and decision making so daunting that they'd rather just pay once and have it done with. They don't know what gear they want; they don't know what classes they want (so they just pay for an do whatever is included in the package, even if it ends up being a Full Face Mask Specialty Course!) I personally don't want my name on a card as the instructor of a DM who can't make decisions about his/her professional training, so those students just self-select themselves right out of working with me!
As for internships for DM courses, it all depends on what your objectives are. You say you want to become an instructor and work with disabled vets. In that case, my advice is to get a good Rescue course to begin with (since that's actually the foundation for HSA--handicapped scuba--buddy and instructor training, IMO). Next, you may not need the same sort of DM internship as a DM candidate who wants to travel all over the world working here and there as a tank-jockey-backpacking-dive-pro does. You may also not need the sort of internship that would put you assisting an instructor working with groups of 8-10 fit adults in a long series of back-to-back courses. In my opinion, if HSA instructor certification is your goal, you would be best served getting a really solid foundation of working with an instructor who does one-on-one training because students who actively seek out one-on-one training often are encountering some barrier to their learning/training/certification, and working through and around these hindrances gives the instructor the right mindset for being able to backtrack and take the time needed to get the student where s/he wants to go.