I had a bougainvillea freeze, killed it back to the ground, and the spouse dug the roots from the trash and planted them and in a few weeks they sprouted and were growing again. So, perhaps, you have no problem except some few delay in growth.

I had a similar experience and along with the freeze it was crippled from a transplant late in "southern california" winter, which translates to it was budding already!!
The majority of the buds died, but now about a month later, the main stalks are budding again and I see new growth on the way! There may be hope