What's stranger is the check byte for the command part is off by one from a normal check byte.

But that whole F50AB54B matches what I see for the second 32 bits.

Maybe Pioneer intentionally made this signal violate some of the rules of the protocol structure (to keep people searching the command set from finding it or to make it harder to generate with some universal remotes).

Either that or there was some copy/paste error in getting the learned signal from the Pronto that learned it over to this forum.

I guess you'll know after you try it.