The star will make a cameo in an upcoming episode
See where the celebs partied this week
The actor goes into arbitration in June for dropping out of a Broadway show with mercury poisoning
Producers are unable to prove the actor caused damages by quitting play
The actor's rep says his Broadway play producers have no basis for filing "outrageous" grievance
Speed the Plow's Jeffrey Richards is upset the actor pulled out due to mercury poisoning
He also opens up about his scary "three days" in the hospital
"It ultimately brought me to my knees," he tells
Us, denying claims that he faked his sickness
His high mercury levels - which forced him to quit a play - also could have been elevated by Chinese herbs
William H. Macy and Norbert Leo Butz will replace the ill star