Though what's there to evaluate, if I may ask: is LLBLGen Pro the tool for you or not, that's what the evaluation/trial is for. So why evaluate a version that's 10 years old, so we don't do that.
If you need a v2 license, you can get one, but after purchasing a v5 license. Besides, I think I know why you want a v2 trial, and I have to tell you: you can't use software made with the trial in production.
Not sure what you mean by this, but if you mean: can they cancel a license later on (so you do the work, use our software and then don't pay anything) then I have to answer: no. They can get a license for you, of course, a v2 if you want, but they can't cancel the license later on. That would be the same as they ask you to do work for them, you give them your software and they don't pay you.
I understand your position, but if you need to do work for them, you can use their license if they want you to, otherwise you have to obtain your own license (either through them, or buy your own).