Why didn’t Shahrukh Khan & Katrina Kaif perform together?

Katrina Kaif was to groove with Shahrukh Khan on stage at a private wedding in London, for which the duo were given a hefty sum. What was the most interesting part was that the two would have performed together for the first time at a wedding function.

As per sources, it was not so, the two were there together but did not perform as a twosome. Shahrukh Khan was seen dancing and later mingling with the guests and Katrina too performed a solo performance to entertain the guests. The only thing that they did together was to stand on stage together for sometime.
The big question is did anything go wrong that the two didn’t perform together?