I do have to wonder (and probably way off base, but hey, hare-brained theories are FUN). I'm thinking that living in a time-shifted bubble for as long as the sisters have, that time itself is perhaps...not quite as solid for them as it would be for others. Making it easier for the 'ghost' (or perhaps briefly, magically time-displaced) toymaker to pass on his skills and tools.

...and if that IS the explanation, there are all SORTS of *very interesting* possibilities, considering how cross-time( and -dimension) Gryphon's life is.