Once you're in OCS (If not BDCP), you are active duty enlisted. If you can not coordinate going to PSD with your wife, then I'm sure she can probably get on base somehow (copy of your enlistment contract and marriage license) to get to PSD to get her ID and set up tricare ETC. This is something that is perfectly acceptable to bring up with your CoC at OCS once you get there, if your recruiter can't help you now.
Don't know a THING about med bills BEFORE OCS paid off. I doubt that since you were entitled to medical care UNTIL you are enlisted (which is when you report to OCS or whenever you swear in beforehand).