Just Brakes fixed brakes but transmission is tampered with. St. Petersburg, Florida

I WILL NOT return to Just Brakes EVER. I took my wife’s vehicle in to the Pasadena (Svc Center #617) for the $99.00 special (which ended up costing me $580.00), I was at the shop from 7AM till 12:30PM, I watched other vehicles get serviced and test driven and they each left and came back the SAME direction and within 2-5 minutes but when I questioned why my vehicle was test driven longer (10-15 min) and came back from a DIFFERENT  direction I was told that the more work that is done to the vehicle the longer the test drive. The only problem that my wife had with that truck other than brakes was that the thermostat was going bad(prior to visiting Just brakes I had AutoZone put it on the computer)and that a few gages (oil and gas) were broken. I took the vehicle home and parked it and it was parked till Sunday morning. Sunday morning my wife took me to church, I received a message from a member of the church that said that they trailed my wife to the house because she said that the car was "acting" funny. After Church I drove the truck a couple of blocks around where I lived and I noticed that it was driving a little sluggishly as if it was hesitating between shifting gears and I thought to myself no big deal it was sitting for about a day and that it would most likely work itself out. The truck was parked Monday (she was off from work and she went shopping with her sister) Tuesday she drove to work and called me complaining that the truck was still acting funny so I told her that we will call Dane (our mechanic) after work, well she calls and says that the truck will not move so I call Dane and he meets me at the truck. Dane looks under the truck to see if the linkage was broken which it wasn’t so then we proceed to pop the hood. Dane checks the transmission fluid and shakes his head and says someone over filled the transmission fluid. I know nothing about transmission fluid and did not know where the dip stick for it was till Dane showed me. No one has been under the hood to this vehicle since my December oil change (December 22 or 23rd) and since then I have been to Tallahassee twice, Orlando about 3 times and my wife drove it daily all over St. Pete and Tampa. My wife has never opened the hood; all she knows is where to put the gas. 

 I am concerned that during the test drive which took a questionably long time that something may have happened to my vehicle.  I contacted the store manager and he denied everything and stated that they did not keep transmission fluid on site but it raises the question why did it take so long for the tech to come back with my vehicle if I had similar work done to my vehicle that other vehicles had done and were test driven and back within a matter of a couple of minutes. Where did he go? What did he do? I can say that I am 100% certain without a doubt that my vehicle was fine before I took it to Just Brakes @ Pasadena (Svc Center #617) 51 S. Pasadena Ave. St. Petersburg, FL 33707. I am highly dissapointed with this situation and would like to have this investigated. 

       Signed,

             Wife and kids without a vehicle