If you are in a situation where work of a particular kind has reduced then you can start redundancy consultation with all affected staff.
The fact that this individual was the subject of a TUPE transfer does not mean that he cannot be made redundant but you can’t select him because he was transferred. Redundancy is firstly about the post, not the post holder.
You need to consult with all those carrying out the work that has been reduced to see if you can find an alternative to redundancy. Bear in mind that even if the post goes it does not necessarily mean that the post holder will go too.
You need to carefully identify the correct selection pool and identify selection criteria for compulsory redundancies if consultation gives you no alternatives to this.
If he is fairly selected for redundancy then you can make him redundant. But you will need to be able to demonstrate that this is for a legitimate reason and that he is not being dismissed for reasons relating to a transfer.