Will the military pay for my BBL

I would not know the answer to that, but that sounds counter to what the federal government would do.

As a rule, insurance doesn't cover cosmetic procedures.  Insurance will cover some things that are considered cosmetic when their is a medical reason a person needs it.  For example, a breast implant in someone that has had breast cancer or a upper eyelid reduction for someone that has failed their field of vision exam.  But a procedure that isn't a medical necessity, i.e. is cosmetic, than they will not cover it.  You're always welcome to work with your in network plastic surgeon's office to try to submit your claim to see what they say.  
Personally I don't take insurance because of the red tape and time constraints.  I wish you the best in your pursuit.  If insurance doesn't work, don't give up.  There are many financing companies that work with all types of credit and offer co-signers.  

Hello justice96 - The Brazilian Butt Lift is a procedure designed to transfer fat from one area of the body, typically the stomach and thighs, hips, knees, and back to the buttock through liposuction. The procedure is meant to reshape, but also enhances the size of a buttock to better fit the figure and provides a perky appearance to rear end. It is unique by the use of the patients own harvested body fat, rather than the use of synthetic material. This allows for a healthier and longer lasting result. Typically insurance does not pay for cosmetic procedures. Next step for you is to schedule a consultation with a board certified plastic surgeon to discuss your options and goals. Best wishes and thank you for you service. 

Insurance companies and government medical coverage such as provided by the military, Medicare or Medi-Cal do not nor should they pay for cosmetic surgery.
This is taxpayers money and that should not be spent on treatments that are not medically indicated.
If you are a male to female trans gendered person it's possible you have a legal right for this type of a procedure.
Still even so I doubt the military would offer the procedure for free.
It's generally better to save your money and pay for a procedure then financing it and paying high interest fees.
This may be a good time in your life to begin improving your personal financial skills by saving some money and then having a procedure.
Best,
Mats Hagstrom M.D.