I thought Kasich has not qualified for the PA ballot.
Kasich is probably not eligible, but the friend of Marco withdrew his lawsuit the day after Rubio dropped out. So we'll never know. I believe the time to challenge has otherwise passed.
PA is a joke anyway, in essence, it's worth less than two territories as far as bound delegates go.
The remaining delegates are directly elected (3 per CD). Not only are they not bound to the candidate they allegedly represent, but you also don't know who they are representing on the ballot.
So unless you walk into the polls with a piece of paper of who supports whom, you are playing Russian Roulette. And even then the delegate in question can change their mind. Sounds ripe for GOP-e shenanigans.
This should favor Cruz and Kasich. Cruz will do a better job of identifying supporters, and getting them a listing of delegate candidates. Kasich supporters will be able to figure out which delegates to support and make their own list.
Trump supporters will be less likely to figure this out, will forget their sheet of paper, or get to the polling place and realize they don't have it, drive home and stop off to eat or have a beer, and never make it back to the polls. Other Trump backers will decide that it is too complicated, or rigged against the little guy and not bother to vote.