I've been hearing about a lot of problems finding the TripKey passes available - both here and on Trip Advisor. I just checked their Facebook page and they have announced that the passes are sold out as of 4/14/18. https://www.facebook.com/tripkeycard/posts/2000407220213919
They said that they would have them in by the following Monday but it doesn't look like that is happening. I think I'm going to forego TK for my mid-May trip and look at buying a regional pass and individual tickets for areas outside the region.