Here is another link to some whelping info. It's pretty basic but easy to read. Maybe you could get them to read it so they will at least be some what aware of signs to look for. This little dog is apparently going to have a large litter and that can be dangerous to a small dog if a person is unaware of what they are dealing with. I know some very expert people have talked to you and I am far from an expert. I hope you can at least get the owner to be a bit more prepared.
http://www.dogbreedinfo.com/whelping.htm