The problem isn't drawing, it was the programming. Getting the leash to look correct on a lot of different characters at different distances in the cell was apparently difficult. (From what I've seen of Unity, I'm not surprised this would challenge a guy whose programming skills are on the amateur level.) He said he was going to draw it in the CGs and just have it not appear in the cells, but that didn't play well (since the dialogue in the cells and the images would be different).
And, like I said earlier, it fits Lex's personality better to have the girls parade at a distance why he stays in the background. One thing SR7 takes pretty seriously is having his character (especially Lex) stay in character.
I agree the scenes would be sexier with the leashes, but I kinda get his decision on this one. This is the kind of thing that might have gotten improved with a professional coder being on the team, but ....