4K Video - digital removal of a loose shirt

The Groom would like the shirt hanging out to be disguised (digitally removed) from the finished video. It comes from a 1st Dance and whilst careful editing has disguised most of it, via cutting between 4 cameras, a few shots it is unavoidable and I have collected these into a 17 second segment, where I need the shirt removed and replaced with some approximation of the Groom's trousers if possible. Either that or some bluring effect to hide it.

I am alas not a master of After Effects, which is where I feel this effect would be best achieved. Or similar program.

Any previous relevant examples, please feel free to share - though I appreciate this is not a normal request. :)

Please contact me for a link to the video.