Starter problems of the 2015 GMC Yukon

Car was parked in covered garage for 2 months. Battery went dead. Attempted to charge battery with 20 amp charger and battery would not take a charge. Attempted to start car with battery booster pack and lights would come on, but car would not start sitting in vehicle with key fob. Console display said that steering wheel was locked. Called aaa and they came out to replace battery. It was the original battery. . . But had worked perfectly when car was parked earlier. New battery allowed lights and all other functions to work, but car would still not start. I closed doors. . . . Hood and then was able to start car with key fob remote starter. Car worked perfectly. Shut car off and tried to start again and would not start normally, but would start fine remotely. Called dealership and they had not heard of this issue, and I made appointment to bring in. Two days before appointment, car would not even start remotely. Only thing that happened was that outside mirrors would retract when I tried to start remotely. Paid $90 to have car flatbed towed to delearship. Paid $234. 99 for dealership to clear all codes and reprogram. Have called GMC several times and they refuse to acknowledge problem or reimburse me. Dealership had never seen this issue before and told me when they spoke with GMC technical department that this issue had never occurred. I find that very suspicious. How could a bad battery trigger a computer to not allow the car to start. This is a very dangerous situation because if I was stranded on a highway and the battery went dead and a new battery or jump start would not allow computer to start car, there could be unfortunate consequences. I have owned dozens of cars with theft deterrent systems and a bad battery that has been replaced has never triggered the system to make the vehicle unable to start. Please advise. Thanks.