Palace sources were telling Dharmesh Sheth last week that Arsenal could still make a deal happen for Zaha if they "get creative" with their bid. Instalments, bonuses, possibly players. They were opening the door.
I'll try to find the tweet, but methinks Palace know Zaha wants to go and will not change his mind and they think getting a decent bit of money so they can get in some quality is the wise thing to do.