Help! What to do about an Ebay purchase?

You've probably read the posts: "Sony won't let anyone sell the 16-50 kit in the U.S., and B&H cancelled my order!" I was in the queue for the 5RL/B but getting tired of waiting; it was back ordered for more than a month with no end in sight, and between those threads and Adorama's Ts & Cs, things were looking pretty sketchy. So today I put in a last minute bid on Ebay for a new 18-55 kit and won. Great, right?

"I'll just cancel my Adorama order tomorrow, and bid on a 16-50"... I even checked my credit card seconds before the end of the auction, to make sure they hadn't charged me for it/shipped anything yet.

Then exactly 2 hours later (to the minute!) Adorama emails me and says a partial shipment is on its way.

Apparently they'll send a 16-50 lens later; they're going to honor their offer (body, 16-50mm, 16 f2.8, SD card, camera bag, gift card)... Great?... Kudos to them for their integrity, and I definitely want this order, but...

Now what?

The auction seemed like a good deal ($530, new body and 18-55, shipping included). The real question I'm asking is, which is riskier:

Try to explain the situation to the seller and hope for them to be understanding, instead of giving me a "negative" (and losing my 100% rating) or: Pay for both purchases (all together waaay more than I planned) and hope to get my money back re-selling one of the bodies and a lens?

Thanks for letting me rant about my stupidity. What are your opinions? (about the orders, NOT about my stupidity;-))

tia