Coolant Leaking problems of the 2014 Kia Motor Sorento

Purchased a used 2014 kia Sorento showing 106k miles. Test drive with the salesman for about 6 miles various types of roads. Very impressed with the car, performed well. Purchased it Saturday afternoon just prior to the used car dealer closing. After paperwork and plates done, drove it toward home. About 4 miles from dealer (interstate highway) saw the temperature guage climbing into the hot area. No other errors or lights came on. Let off on gas to pull over and temp guage came down to normal. Continued with caution thinking this was a faulty guage or sender unit. Limped home slowly. Noticed going up hills and pulling hard temp would climb. Letting off gas temp would drop to normal. Long story short got the car to a very reputable and experienced garage. Engine couldn't be repaired economically. Dealer did offer money back. As much as I didn't want to, wound up having to install another used low milage v6 engine. During the month in the garage I had done much research & digging & talking often with the very experienced mechanic in charge of the job. Coolant was low and all but two of the head bolts were more than finger tight !! how this engine was running was beyond me, it was! during all this research I read of many head gasket problems and leaks had been reported. The thing that was really concerning was the number of engine fires that had no real cause reported afterwards. My concern is if I had continued driving this car hard, could a leaky head gasket cause a fire under the hood? I learned from the mechanic all these head bolts stripped the threads from the block. I also learned there is another 1. 5 inches of unused threads inside the block! my suspicion is kia skimped on the length of all these head bolts to save a buck putting the reliability and safety at the customers risk. Is my safety at risk? where is my recall for this car engine? 12/09/2019 dd.