2010 Toyota Corolla**cursed car

I have a 2010 Toyota Corolla. The VSC Light and check engine light came
on. It has done this before and we replaced the spark plugs in two of the
cylinders and it fixed the issue. Fast forward 6 months, and the car does it
again. It's "running" very rough and two of the cylinders keep misfiring. The
first Mechanic said it needed a whole new engine because the head gasket
blew. The second Mechanic said the head gasket is in good shape. He did a
tune up, but the cylinders keep misfiring, (original problem). The Toyota
Technician spent some time on it and said it's electrical, but they can't
identify where the problem is coming from and it's a money pit at this point.
HELP! I still owe $4700 on the vehicle that I can't drive.