Muldoon put in some impressive performances in Derry's run to the 2007 All-Ireland quarter-final, where they lost out to Dublin. He was awarded the Ulster Tennent's Monthly Merit Award for July 2007, for his performances against Mayo and Laois that month, including a lobbed goal against Mayo. This was the second time he had received the accolade. He was instrumental in the 2008 National League, which Derry won, defeating Kerry in the final. Joe Brolly described him as "the best player on the field". The league success saw Derry become favourites to win the Ulster Championship and one of the top few for the All-Ireland. However, despite a good opening victory against Donegal, Derry exited the Ulster Championship against Fermanagh at the semi-final stage and were defeated by Monaghan in the first round of the Qualifiers.