I don't know why they torture a dead horse in the hope that the project will survive? Are there projects that have recovered after the hack, but I think there are no such projects.
There are some like ETC which suffer 51% hack but manage to recover. I believe this is only possible because they are already established but for startup project like this pancake bunny and poly network, Recovering after this huge loss is almost impossible, the team already loss funds for development and no VC will gonna lend again for this project for the second time considering the risk of losing again.