Tableau doesn't have built-in density, distribution, quantile, and random generation functions for the different distributions.
This would be a good use of the R integration with Tableau, calling the R qchisq() function via the Tableau function SCRIPT_REAL().
Bora Beran is a Tableau employee and he has written some posts about this integration. He includes good examples. A good starting point is here.
I look forward to reading other, possibly more useful, replies from other members of the Tableau community.