
The fact that she would cross breewd her chi's (and if registered ones are more expensive why would she do this) would make me very suspicious.
Why did she not simply mate them to the appropriate breed?
It could even be that she has not even got a smooth and long coat but has used one of the Yorkies (far more available and easier to breed with larger litters) mated to a Chi male (easier to get than a bitch when with litters of ones and two chi females are like Gold dust).
Of course a breeder, especially in a toy breed where the dogs take up less space may be specialising in more than one breed, but most people find one or two breeds the most they can devote themselves to.