I think you need to have it checked by someone OTHER than the repair facility that did your fan repair. My fans, triple the output of the OEM, were $4.97 EACH. There's other checks to be done.
What did they do to determine your fans needed to be replaced in the first place.??
Disconnecting the thermister, (unplug the connector by the light) will force the fridge to run all the time. Using a GOOD thermometer, check the temps after 1-2-and 3 hours. If the box temps fall, the thermister is bad. Easy fix.
Are you running on A/C or LP..?
Have you reset the box? Remove the 12V wire, wait 30 seconds and plug it back in to reset it.
Have you checked the 12V supply.? There's a fuse inside the black box.
Let us know what you've done so far, trouble shooting wise. The dealer ripped you off...Dennis