None of them are obliged to release bupkis.
Cruz and Rubio need to release all of their return before demanding anything from Trump.
Cruz should also unseal his immigration information.
I for one would like to see Trumps college transcripts. He claims he made really, really, really good grades.
Kind of hard to unseal a file that doesn't exist; especially since even 2-3 courts have already ruled he is qualified to be President; or did you miss that?