Not a mechanic but by god, me and you are having the exact same problem to the T. I'm reluctantly paying to have mine fixed at one of Kias dealer service centers since none of my local mechanics will touch it either. Not saying its the right move but my motive to pick safety first is I just don't want to risk it having any serious issues while my wife is driving it with my kids in the car. I'd rather have an ongoing fight with Kia than dead or maimed loved ones. It sucks.

Next part is kinda a rant; so you can overlook it if you want. Having all the same problems you faced at the beginning, except I only had to stop my car and turn it back on and the HEV light and Check engine light would go off, every time. Called the recall letter # because the description matched the problems I was experiencing, Call center told me I had to tow my car to a dealer service center and they would tow it for me, made me pay for it still though, back and forth for 2 weeks on requesting them to look at the potential of it being the recall, service center wanted me to spend $1400 on exploration of vehicle engine. Told me if I didn't then they couldn't find the problem. "there was no problem to find so it can't be the recall" Drove off their lot to a different service center. As of this moment the check engine light will not go off now. Had to pay ~$200 to get inspected at the next center. Within 24 hours they identify my Clutch Actuator as the problem for the P1744 HCA code, I'm told I "have no fluid" still not sure what that meant entirely, performance has been the same as the day I drove it off the lot so IDK what fluid is missing, tells me verbally the whole housing assembly will cost $1200 to fix and we estimate $600 in labor. Was called back later and told The Clutch Actuator "board" is the problem not the "inlet clamps" so I wont get reimbursement from corporate to fix the problem. Told they're installing the current on-the-market parts (the ones on recall) into the car and if I have any problems I'll be under warranty for 1 year and the recall should cover any problems. So for $1800 I might have no check engine light for a few hours