My suggestion - it's likely the lock pin that locks the steering wheel is frozen in the upper casting where it has to slide into the lock plate. I've seen this before - you can't turn the lower locking lever on the column until you get this freed up. Cause of the problem: either dry lubricant, no lubricant, and dissimilar metals/corrosion (steel pin, aluminum casting). Take the steering wheel off, the upper cover if equipped, locate the pin where it comes out of the casting to interface with the lock plate, and shoot it with WD40, PB Blaster, Kroil Oil, or another rust corrosion breaker, and work the lower lever until it's free. Betcha it solves your key problem (it did for me). Gotta remember, lubricants after 40 years or so tend to set up like concrete -
Regards