Today I saw only the unsterilised female, the sterilised mother cat and one of her kittens.
I managed to get the female into the carrier and then waited a while but no sight of any of the other cats. One of the guards said that he saw them yesterday, and that they will come out in the evening. I also asked about the older injured male... he seems to be better.
After some time, the young ginger-white male finally appeared and I trapped him and called Damy. Both cats will be sterilised under SPCA vouchers, boarded and returned on Tuesday.