Group module is a disaster.. now what ??

I'm in my 40s studying my Master's. One of our modules is "group work" where we have to build a portfolio and submit a piece of evidence as a team.

My group has not only done no work at all, but kicked me out of the group without my permission. The university staff then explained I had left on my own accord, and this meant I had to start completely over from scratch, do the work equivalent to ALL group members - and with 2 weeks before the submission date. The day before I had spoken to my usual lecturer and they had said nothing about this.

After a lengthy discussion we finally determined the group were not allowed to kick me out, the university staff were not allowed to agree, unless there was plenty of evidence to justify. This is impossible because I am the only one who did any work, plus offered a lot of support, despite being the only part time student with other commitments. The university staff have accepted all of this, and replied that I can apply for PC, but I don't see what my circumstances have to do with it.

I'm really not happy with the level of academic rigour here. I did explain multiple times that the lack of work from my groupmates (who are nearly 20 years younger than me) was very poor. The uni explained they were not willing to enforce any standards. Then they've turned around and given me an impossible deadline. Any advice on my next steps with this ??