If you have not accepted the SCO, the seller will not be able to leave FB. What the seller is trying to do is called Circumvention of eBay fees. The seller will only get charged for the $99 instead of $205, should you accept the offer. This is clearly a violation of eBay policy and you have all the right to REPORT!
If the seller is new and what she said about not knowing how SCO works, then there is a possibility that when she send out the offers, she check marked all the bidders for the auction. Thus, multiples SCOs went out.
I think the best action now is to write back to the seller as mentioned in (A). Frankly, a negative FB hurts a seller more than a buyer and you can always reply to a seller's negative.
I am going through a terrible eBay experience myself now and the worst part is the item has already been paid for and shipped to me.
Good Luck to you!
I had accepted the SCO via ebay actually and then later on I received the email from the seller. Snapcat said that the seller wrote to her directly, so I don't think the seller "made a mistake" of sending out multiple SCO to all the bidders. Something just doesn't seem right, even though I do not want to speculate anything at this point. I will just write to the seller and see how things work out. Heck if she gives a neg feedback as you all pointed out, she has more to lose as the seller.
I am really sorry to read about the problem you have with the citta rosa ciao ciao. Hope things work out for you in the end.