Diddy raked in more dough for another New Jersey club appearance this week — but this time, he didn’t even know why he was there. The hip-hop impresario collected $150,000, sources said, to perform at the second anniversary of the W Hoboken’s Chandelier Room on Wednesday night. But halfway through the show, Diddy shouted from the stage, “Let’s officially open the roof at the W!” Told that the W was 2 years old, he said, “It’s been open for two years? Where the hell have I been?” Party organizers looked panicked. “I didn’t know it was the second anniversary,” Diddy said. “Feels like the grand opening.” Sources said he made his way there without a police escort, after the scandal over his appearance at a West Orange club last week. The sources also told us Diddy often hires off-duty cops as his concert security. Diddy’s rep declined to comment, and an NYPD rep didn’t get back to us.