Service tpms warning

Yes they could have damaged one of the sensors or generally screwed it up. 

However, the Jimny "re-learn" process for the TMPS is notoriously unreliable. On the assumption that the wheels didnt not go on the same hubs when reffitted to the car, the TPMS has to re-learn where the wheels have moved to. It is getting the signal from the sensor but it will be calculating it is in a different position.

This learning process is for 10 minutes after commencing driving (fast learn period) after that period it goes into slow learning.

During the 10 minute period you have to drive as straight as possible and at a constant speed above 14mph (i think) so if you pull out straight into traffic you mess up the relearn. So choose your road carefully.  If the relearn fails you have to start again but you must have a minimum break of 20 minutes of stationary with everything off (Suzuki suggested 2 hours would be better but the manual says 20minutes).

ANother way of doing a relearn is if you have a TPMS activation tool and ping the tyres with it in a set order after starting the learn period.

THE alternative to all this is just to keep driving. It will eventually sort itself out. (if the sensors are actually working).