If it was me, I would follow in other people's footsteps that have been in the same spot and get out of Mexico with a piece of paper that would allow existing Mexico minus the danger of getting the auto confiscated at a roadside SSP Reten.
It means going to a larger town or city or the best is a port that has an office of ADUANA. Explain the problem. They understand and won't play dumb.
The will issue you a get-out-of-jail-almost-free card. Almost free because I believe the work costs 750 or a thousand pesos payable at a bank. I do not believe the paperwork needs to be turned in at the border (what would be the point?)
Since the infraccion is computerized it will stay in the memory bank forever with your passport number being the flag against getting another TIP. Change cars or getting another driver license does not help.
I do not know what the current status of Retenes is on Mex 15 or 57, but if you get processed, the minute they check the registry in Mexico City on a laptop, the data is red flagged. The cops had better come up with your vehicle. So attempting a bribe is futile.
