As noted doubling is of course way out, Blue has only 8 rolls to win, White may cash the rest, leaving Blue a huge money underdog with equity (8 − 28)/36 = −.556 . Thus it seems correct for White to beaver, and as the equity is less than −.500 Blue would do better to drop the beaver than to take.

So for ordinary money play, the correct action would be no double / beaver / drop, but here there is an additional factor which complicates things: The cube cannot exceed 64, so if Blue raccoons White's beaver the cube is dead.

This means that if Blue's cubeless equity is better than −.250 raccooning the beaver is a better bet than dropping. Also if Blue's cubeless equity is better than −.139 White will do better by not beavering and keeping access to the cube, than by allowing Blue to kill the cube by raccooning.

Doing the math we find Blue's cubeless equity to be −.203 meaning that with PB's maximum limit the correct cube action is no double / beaver / raccoon !!