That's the only way the participants will get any kind of significant reward now in exchange for their early support.
The keyword is promptly. In two months nobody will want them even as basement heaters.
Well, maybe for $80 or so, but anything above that is a waste of money as you can get other electric heaters at Walmart for similar price.
The 17+ BTC price was probably generated by their wonderful system. I don't imagine Yifu to be such an ignorant prick to ask for that kind of money after 5 months delay.
If he did enter it manually and wants that kind of money, he might be a megalomaniac and should check himself to the closest mental walk-in clinic.
Yifu, be a man, admit you fucked up, return the boards/pay the cost of them or send free avalons.
Do it, do it now before you lose all credibility in the bitcoin community.