Yah it's probably close.

risk 993 for 264 dead money.

needs to fold to shove X%

If we have worst case 25% vs calling range to shove
X(264) - (1-X)(0.5)(993)=0
264x-496.5+496.5x = 0
x = 65% folds

If we have 35% vs calling range to shove
x = 53%