I don't think anyone was being nasty on this page we are all dog lovers and put our dogs first their welfare is our first priority. If you google leaving your dog alone all suggestions are get a dog sitter/walker for owners overnight stays. Any longer put them in a kennel or get someone to stay at your place or take them to theirs. Under no circumstances is it acceptable to leave them longer than a few hours 6 being the limit on their own.
I would not put a 6 hour limit on leaving a dog alone. If he has the run of the house and yard, lots of dogs are at home while their owners are at work, and they do fine. It depends a lot on the dogs age and temperament.
When I go away, I prefer to leave my pups home because I think it's safer and less stressful than a kennel. But I have people who come to the house three times a day to play, feed, water and give them time outside.
Reschedule the holiday...compared to a the needs of a labrador puppy, it is not really important in the grand scheme of things.