Chris, did you pre-treat the L. cheesmanni seeds? These and others from TGRC can be difficult or impossible to germinate without treatment, although they are viable.
I did not manage to germinate some Lycopersicoides accessions last year with ordinary treatments, (Pimpinellifolium germinated but took weeks) so this year I followed the method recommended by TGRC using half strength bleach (which is pretty extreme!), and the stubborn ones are up 4/4 this time, also as quickly as tomatoes.
Check it out if you hadn't seen it:
http://tgrc.ucdavis.edu/seed_germ.aspx