I would say as long as a freeze cube is on top of a cube, it's frozen.
Did you or your opponent knock your freeze cube onto your cube? That had to be a crazy moment, the kind that make me love this game.
So you think your own freeze die can freeze your other dice?
You may be right, I don't know exactly what the rules mean by 'knocked off'. Knocked off the original die/dice or knocked off of the any dice
I placed a die on one of my wife's that was on my side close to my King.
I can't recall whose turn it was but the end result was my freeze die getting knocked off her frozen die and ended up on top of one of my own die.
I think we ruled once a freeze die is knocked off of its original die/dice, it comes off, but again I'm not 100% certain