According to this site...
http://www.taxhistory.org/www/website.nsf/web/presidentialtaxreturns
Ted Cruz and Marcoverclocked Rubio have not released any of their tax returns, but Jeb, Hillary, Bernie, and Carly have.
Are you absolutely sure Cruz has never released any of his tax returns?
May I see your data on that?
The link you provided does not address whether Cruz has or has not released tax info. Read the text of your post again: The Tax History Project is currently compiling a more complete archive of candidate returns, and we welcome suggestions on who to include and where to find additional returns.