Creedence Clearwater sold over million records BEFORE Woodstock and millions of records AFTER the festival. 

Proud Mary started to climb higher on the charts already in January-February 1969 - no less than half a year before the hippies gathered together at Max Yasgur's dairy farm. 

Of the singles the band released after Woodstock, six went straight to Top 10 on charts. By late 1990's, Creedence Clearwater had sold appr. 80 million albums in total. All this without appearing on the film. 

It's doubtful, whether the absence on the Woodstock film had any real impact to the band's career.