" I will do my best to buy it back."
OMG! That is theft on their part. IT can be rebuilt. Get it back ot your house or someplace they can not find. They have no right to seize YOUR vehicle and hold it hostage. Watch them have it destroyed behind your back.
Check with the police and see...
Both insurance companies work together to cheat the customers. They make less money if they pay you more.
I would not accept the "totaled" opinion. Get it out out impound ASAP. Possession is 9/10ths of the law.
Gather comps and send them. Do not settle. Bring in the personal injury...