Cuddlepie,
Sorry for coming so late into this threat - what a tough time you have been having
. My advice is go with your gut - it you dont want to go the surgery and you want to give the treatment a go - then do it even if it means a stint with another FS - you can always do the other if you have no luck with the one you go with first. It is your body and you are the only one who can weigh up the risks - physical and mental as they apply to you.
I cant offer much, especially about the treatment (my implantation issues were due to ANA antibodies not NK)...but my only piece of advice is that if you go down the treatment path to ask your FS, or prescribing Dr about clexane vs heparin - they both do the same thing, but have slightly different side effects. You may also find that you start on one and then get switched to another. The main advantage of heparin - the injections hurt less, and the blood thining effect is reversable (which is why if you have to continue close to the third trimester they often swap you to heparin in case you need an emergency c section or go into early labour), on the up side for clexain - only one injection per day and I think less side effects in terms of long term use and osteoperosos (sp!).
Good luck.
FG