Replacing a radiator is very much independent of just about any other part of the cooling system. I've been a mechanic for 25 years, so quite sure about that. As such, I'd say you #3 scenario is quite unlikely. A radiator replacment is quite a traight-forward job. Not sure why it cost you $3k, but either way, it would not affect the engine or heater core, etc.
What is believed to be the problem with your engine? Are they suggesting a blown head gasket or it there something else? Also, cololing smell in the vents starts sounding like heater core and realted plumbing.
Did you car overheat after you cracked the rediator? This could cause a blown head gasket and some cooling system issues.
What is believed to be the problem with your engine? Are they suggesting a blown head gasket or it there something else? Also, cololing smell in the vents starts sounding like heater core and realted plumbing.
Did you car overheat after you cracked the rediator? This could cause a blown head gasket and some cooling system issues.