Hi and welcome to YT
.
To be totally honest, I would not take this puppy under any circumstances that the breeder may claim to have. It's irresponsible on the breeder's part, and it'd the same on your part as well, to be frank.
If you do end up taking it regardless that it's not the right thing to do for this little puppy, then I guess it's a life or death risk you're willing to take. Personally, I would not put a living creature in this sort of vulnerable situation.
You need to read this thread:
http://www.yorkietalk.com/forums/gen...ent-guide.html
As far as feeding, feed whatever the breeder is feeding and do NOT change the food until this pup makes it until about 14-16 weeks old. Have Nutrical on hand and give it before bedtime, and right when they wake in the morning...and perhaps a couple times btwn meals. Free feed the kibble.