I don't really see the problem, you worked for a company, they have to pay you, if they don't just sue them... I mean, definitely is not your (direct) problem

I don't really see the problem, you worked for a company, they have to pay you, if they don't just sue them... I mean, definitely is not your (direct) problem if the client haven't pay yet and is not your fault neither that you missed the deadlines... I would just be straight with your manager...