If he could see what they've done to the company, he'd be rolling in his grave.
Если бы он мог видеть, что они сделали с компанией, он бы переворачивался в своей могиле.
Definitions
To express the idea that a deceased person would be extremely upset, shocked, or disturbed by something happening after their death, often because it goes against their values, beliefs, or wishes.
