Liz, Does it bother you? If not, then let him have hope. If there is a pothole along the way with poor test results, he will have to deal with that then. But it sounds like he has had some very down events recently. I cannot imagine living with this disease and go through what they do day by day. Diet restrictions, fluid restrictions, all the meds they take, being connected to a machine for how many hours a day and how many times a week. Well actutally I can, my dear deceased MIL did it for 3 years while in her mid 80's. Still miss her and it has been 5 years. She was not a candidate for transplant, bad heart.
Maybe he just really needs this right now. He may have the cart before the horse, but then, it is his cart, haha.
Please do talk with your co-ordinator and your appointed advocate to get your feelings sorted out about this as well. It isn't all about the recipient, you are the one that will make it happen, but, be sure you are truly ready to make the life commitment that follows donation.