Tri Care Ins

Help! I am 26 months out from an Lap RNY. I have lost 135 pounds. I need to have a TT but from what I've heard, I can't have a full one due to an old sub costal gallbladder incision, which is fine with me, I just want my roll (Panni) below my belly button removed. I have "documented" rashes with my PCP. I am on SSD from an auto accident so my primary ins is Medicare but my husband is retired AF so my secondary ins is Tri-Care Prime. I had no problem getting approval for my gastric bypass, but I need a letter to go by so that my PCP can send it to tri care. PLEASE does anyone have or know where I can get such a letter to go by. My PCP is not familiar with all this, but I know Medicare and Tricare has paid for" reconstructive" surgery before. I did have a members profile on my "favorite's" with all different type's of letters but I got a new computer and it got deleted.