I'm wondering this myself. I wasn't planning on crafting another wolf but I also didn't want to 'waste' the keys I had so... I crafted a couple chests and am now very near to crafting another wolf but I don't feel like using my energy to do finish it nor do I want to use my gems since I'm going for the second fawn, too. If I could open one chest tomorrow it'd give me enough for my final wolf without me having to deplete my resources anymore than I already have. I'd much rather end the event with an extra wolf than an inventory full of coins, ya know?
Only saw this after I posted so thanks for pointing that out, I haven't been checking the goal book so I didn't see the timer. I think it's silly that it's ending earlier than the event but what can we do? I guess I'll have to see if I can make those last three gold coins on my own.