Band cancelled gig on August 13 but drummer now says he is "feeling better than ever"
Performance in Concord, California was cancelled due to "ilness"
The Hollywood star played guitar on a rendition of 'Train Kept A-Rollin''
Final day of metal festival also brings performances from Against Me, Alter Bridge and Black Stone Cherry
Artists team up for series of live dates in the US and Canada this summer
Calling Festival will take place on June 28 ad 29, 2014
US band will close three day festival in June of next year
Singer says band began jamming as they waited for drugs to arrive
Aerosmith were due to headline festival in July
Elton John also receives special award and Smokey Robinson debuts new song at the New York ceremony