The two pop superstars were involved in a row over backing dancers.
Judge Simon Cowell described the final as the best he had ever seen.
Culkin plays Roman Roy in HBO’s acclaimed family drama.
The couple tied the knot in 2009.
The man, a massage therapist, sued the Oscar-winner for sexual battery.
The couple already have four children together, and Alec has a daughter from his previous marriage to Kim Basinger.
The singer had three sons with her late husband Rene Angelil.
The singer said she had always sought his approval.
The beautician said fans were keen on the pair becoming an item.
Ferdinand’s wife Rebecca died in 2015.