Wilkin had not played since breaking his thumb in July, but his return helped Saints end a four-match losing streak.
"You saw the leadership that Jon gives the team and I thought Luke Walsh was phenomenal and Alex Walmsley just gets better every week," Cunningham, a former Saints captain himself, told reporters.
"We were really determined tonight, I could see it on the faces of the players in midweek.
"A few people like to kick you when you're down but we're together and we quite like the idea that everyone had written us off."
The win leaves St Helens fourth, level on 34 points with third-place Huddersfield Giants.