Tunnel Blocked, not lava

[Timman24]

I made it to the tunnel down by the platinum but the tunnel entrance is blocked by brown rock that is on the upper portion. I can't crouch and the dynamite doesn't do anything to it. I have the fully upgraded drill and it doesn't work on it. Are the caves randomized where it could potentially not be accessible? Thanks!

[Racer]

Caves are RNG based yes. It may be how the dynamite is landing. the only thing that cant be blown up is the gray rock/metal looking ones