Sounds like an issue with the class Leo. Every Judo class I've been to does Uchikomi. Everyone does it, from beginners to advanced students. The advance class sounds more like a randori based session.

See if you can find a training partner to drill Uchikomi with (no throws!) before class. Or worse case scenario, look for another Judo class. Your experience isn't something I've went through, it could just be the school you are with doing things differently.

Just a hunch, but does a different coach take the beginners classes and the advance classes?
"Let your food be your medicine, and your medicine be your food" Hippocrates.