These are some seriously warped appraisals. Expire.com. Nice domain, no question. Very nice.
But $xxx,xxx? No way. Who's going to pay that much for it? One of the folks who appraised it? Nope. There isn't some domain fairy in the sky that comes down and buys domains for 8 million dollars just because they're a decent one word .com.
Look at the word expire. Low google for a one worder, low overture, low paying keyword. As far as the credit card or domain argument..well, they're both flawed.
Why would a credit card company want a domain called expire.com? I don't see that.... As far as a domain company - I assume we're talking about a droplist service or a backorder service? Wouldn't expired make more sense? The domains are expired, not expire. Past tense. Also, why would they shell out 800 million dollars or whatever the appraisals were for up top for something that doesn't mention their service? Expire isn't very descriptive.
Realistically, if you can get a $12k+ offer, you're doing very well and would not be wrong to take it. You could possibly get $25k, just by the innate deception of a single word .com, but I wouldn't count your chickens. The domain is NOT worth that, but it could sell for it.
This, of course, is my opinion, and it's a great domain, but please don't buy a Porsche because these appraisals above say you have a $xxx,xxx value domain.
Good luck!
-John