went to CCRM but did not opt for the guarantee - our situation was different though (had an outside donor). It did work first try there to my surprise with a single embryo tx. Had many failed cycles elsewhere with the same donor.
FWIW I had also tested positive for high NKs and some other things, but CCRM did not think I needed IVIg or intralipids or LIT (I had done those over the years with failed cycles). They did continue lovenox and folgard, added vitamin D and electroacupuncture.