Walsh, 32, was pictured holding Atack’s hand at a London pub in 2016 while he was dating actress and playwright Rebecca Humphries.
The comedian was this week dumped by Humphries after she discovered he passionately kissed Jones on her birthday while she sat at home alone.
Humphries, who starred in ITV series Cockroaches, called time on their five year relationship in a blistering Twitter statement in which she accused Walsh of being “controlling” and calling her a “psycho” whenever she voiced her concerns over his relationship with Jones.
She insisted she is not a “victim” but a “strong ,capable person” and finished by announcing she is taking full custody of their pet cat. She wrote: “I hope he gets what he wants from this. I’m not sorry I took the cat though.”
Walsh and Jones, who is married to fellow Strictly pro Neil Jones, both released apologies in the wake of their kiss.
Walsh apologised for his “actions,” branding it a “one-off drunken mistake,” but he was criticised for failing to acknowledge Humphries in the statement.
Katya insisted she is “very happy” with Neil and that the kiss is “not a reflection on [their] relationship”.
Strictly fans called for the pair to be axed from the show in the wake of the scandal, with some calling for recent evictee Lee Ryan and his partner Nadiya Bychkova to replace them.
It is unclear if the 1920s dance was the original choice for week four as it was reported they had changed the routine to be less “sexy”.
Standard Online has contacted representatives for Atack and Walsh for comment.
Strictly Come Dancing is on BBC One, Saturday at 6:40pm