Help! Advice on capturing injured feral

Hi all. This is my first post here in this community, and I'm desperately in need of some advice.

my partner and I feed my neighborhood ferals, about 5 of them total. We have a few cat houses for them outside of my back door, and a camera set uo so we can see who is coming and going. They are very skittish and bilt when they hear the slightest sound.

On Saturday night, I noticed that the tuxedo cat seemed to be walking a little oddly, but I couldn't get a clear look. Tux didn't come around again until late yesterday (2 days later) and spent the whole night in one of the cat houses. This time I could see clearly that they were dragging their back legs.

First thing this morning I tried to sneak out and block off the cat house entrance so I could trap it and get it to the vet. I had no luck, Tux very quickly crawled away into the darkness. I didn't expect them to be so fast with their injury.

I have a trap that I could use, but I'm afraid with the way Tux is dragging their back legs that the trap may snap shut on them, and cause further injury. I'm also not sure how to avoid trapping the other ferals by mistake... or the oppossum or raccoons that also stop by to eat the cat food.

I feel horrible that Tux is out there scared and suffering, and just want to get them some help. What is the best way to go about capturing Tux so I can take them to a vet? I would greatly appreciate any advice or suggestions you may have. 🙏