Even though we have 4 dogs of our own, we met with a dog owner that was very upfront with her dog's lack of socialization and his aggressiveness towards other dogs. After a very thorough meet-and-greet, we decided to watch him, knowing that I would be constantly watching every interaction, had the means to segregate the dogs, and knew that it would be beneficial for him to get that socialization time in. He did great during his stay! There were no incidents, and by the next day, he was part of the pack and socialized with the other dogs like he grew up with him.
Agreeing with the other responses, yes, there are sitters that will take an unsocialized dog, with or without other dogs around. If there are other dogs at the residence, be prepared for a long meet and greet. Meet with several sitters, make sure it's a good fit. It can be worth getting that socialization time in while you're away!