RIs are fairly few & far between currently.
Please pick up a copy of Alan Beer's book "Is Your Body Baby Friendly?" Start there. It is a good reference book & starting point for immune issues.
If you are in NYC, you might consider a consultation & testing with Jonathan Scher as a starting point. He is an ob/gyn & does most of the testing & treatment the Beer Center & others do. A friend of mind who no longer posts here did immune treatment through him while doing a DE cycle on the west coast (she's in NY).
I'll be honest - she wasn't the biggest fan of his personality & she also had a run-in with staff at the Beer Center in trying to consult with them, but she had failed DE cycles & wasn't taking any more chances, so she did succeed in her DE cycle on the west coast while working with Scher in NYC on the immune stuff.
I've followed your story & I really think you need to do further testing before any more ivf cycles. Has your dh done sperm dna fragmentation & karyotyping? What testing have you done?
I know CNY uses intralipids, but my understanding is that they administer it once right before ET? Is that correct? I applaud them for dipping a toe in the immune arena, but I'll be blunt here - if someone really has a high NK problem, administering a dose of intralipids right before ET is too little too late. Your body needs to be calmed down & receptive ahead of ET, & you really need to know what your body is doing on that intralipid dose. We're not all the same. Some people need more aggressive treatment than others. And I'm speaking from personal experience here, as well, unfortunately.
I'm really sorry about your sister. Is that like her or is her condition to blame? That's harsh & you shouldn't be treated that way. I hope it's out of character for her.
I know you're with CNY for cost, but can you travel or pay more? Also, what has the quality of the embryos been? It can certainly seem like failed cycle after failed cycle = something more with you, but maybe not. Were these frozen eggs or donor embryos, or from your dh's sperm? If the quality has been poor, it could still be the eggs or the sperm, with you never having had a real chance yet.