Katona split from Mark Croft last month after hearing that he had partied with strippers during a family holiday.
The women in question later made a number of allegations about his behaviour in a tabloid newspaper interview, though Katona is believed to have reunited with her husband regardless.
Reflecting on the revelations in an interview with the Daily Star, McClarnon revealed: "I love [Kerry] to bits. If those lapdancers hadn't exposed Mark, someone else would have done. He's a married man. What's he doing?"
McClarnon previously expressed fears for her former Atomic Kitten bandmate's wellbeing four weeks ago, describing her as "not okay".