What you're saying doesn't make sense.

Fake Friends (Chris) already has a nude photo of Anna. He'll deliver it to the Man in Underpants (Lonard). We just need a new pair of Anna's panties. So the Man in Underpants (Lonard) can tell him what David's fake infidelity looked like. Why would Lonard take Anna's panties at a poker game? And get nude photos from Rob? Then Lonard won't need Chris anymore and won't tell him anything about David's fake infidelity because he'll have nude photos of Anna from someone else, as well as a fresh pair of panties. Rob will more likely steal Anna's fresh panties. Because he's a frequent visitor to Anna's house when she's away. Or he could steal them during Anna's massage or ask for her panties like a trophy. To annoy Chris.