I would probably have taken them all for a walk around the block together first, as bringing a dog into the home sometimes causes trouble. Most pups aren't lucky enough to mix with other dogs, so 10 weeks old isn't really a long time since leaving their littermates.
I think splitting the pups up was probably for the best especially as one was trying to be dominant to the other. Pups are constantly trying to dominate each other, sometimes it sounds pretty rough, so the lab probably thought "yippee!!", and just ploughed in there.
Hopefully if you meet again, he will be more socialised and better behaved, maybe take them all for a walk first?
I think splitting the pups up was probably for the best especially as one was trying to be dominant to the other. Pups are constantly trying to dominate each other, sometimes it sounds pretty rough, so the lab probably thought "yippee!!", and just ploughed in there.
Hopefully if you meet again, he will be more socialised and better behaved, maybe take them all for a walk first?