Installing hook on strange wall
This sounds like old school plaster on metal mesh, common for that era in apartments and condos. Hard as a rock. However, you'd have to open up the wall to find the concrete block that's most likely behind it, because the plaster is only supported by furring strips tacked into the blocks with nails. Do not be fooled if your stud-finder scores a hit. Don't be surprised if you find none, they're probably small metal c channels.

I would not employ "any other methods" then the appropriate lag screws into a wood stud or masonry fasteners into their appropriate substrate.

Long story short, installing this correctly in an apartment of your construction is unlikely. You'll shot your eye out, kid.