@withersailor

I look it up and they have developed a specialized training facility that helps promote wildlife skills in the cats:

What is meant by pre-release training?

Our pre-release training programme is our way of developing the necessary life skills that the cats will need for life in the wild. It is important to note that it is illegal to feed live prey to the wildcats. Instead, the programme will include the development of tools (e.g. automated feeders, lures etc.) that will help promote and expand key behaviours, as well as physical and mental fitness. Key behaviours include hunting, foraging, social interactions and avoidance toward human presence.

Before release, the wildcats will have veterinary health checks to ensure they are free from disease and physically healthy.

I wondered the same. Also in captivity, all their feed is dead animals. How good are they going to be at getting food when their prey is alive?