Cindy's Answer

This doesn't sound like classic separation anxiety, this sounds like a young dog who is overstimulated and excited. I would not continue to take him there if this was my own dog. I would expect this excitement to become more pronounced as time goes on.

Personally, I'm not a fan of daycare or dog parks for my own dogs. (I have Malinois and Cattle dogs) For some dogs, it may be fine, but for my dogs, it puts them in an overly excited mindset that is detrimental to the type of behavior I expect. The more you let him rehearse the crying, whining, and nipping at people the worse it's going to get.

Ultimately the choice is yours, but I foresee problems if you continue with daycare for this particular dog.