Hillis came under criticism for allegedly skipping a Halloween event at the Cleveland Boys and Girls Club on Monday, according to the Plain Dealer.
LeCharles Bentley, a former Browns lineman and board member of the club, got a commitment from Hillis' brother and business agent to appear at the event, which was then promoted in the local media. Another source told the newspaper that more than 40 kids were on hand.
A text message to Hillis' agent asking for comment was not returned.
A Browns spokesman had no comment other than saying that the appearance was scheduled and promoted independently of the team.
The Madden cover man and 1,000-yard rusher from last season started this campaign unhappy over his contract, and has been in and (mostly) out of the lineup due to hamstring problems and strep throat.