Why wouldn’t you go back as soon as the weather cleared (even if you had to take a day off work)?
First of all, if he was even remotely familiar with hiking that area, he would have been aware of protective measures for his dog, including booties.
Second, if he left her there for eight days and nights, he obviously was banking on her not surviving. If so, then he is a coward of the first water.
Third, if this goes to court, I hope he is required to give her up, and is ordered to never own another animal.
If I loved my dog, (I don’t currently own one) I would have done everything possible, including going back up with a friend or two to THE VERY NEXT DAY to bring her back down. No way would I have allowed her injured, starving and thirsty to endure all that time unable to help herself.
But don’t get me started.