I can understand not wanting to fight for backpay you realistically have 0 chance of getting. It's similar logic to someone insisting you sue person X when they clearly have nothing of value to their name and you'd end up spending more in legal fees then you'd get. And hey, for what it's worth, it sucks you got scammed like that.
But that's why I'm disappointed you haven't done anything about it and were continuing to endorse Brianna up until the end of the election. Don't you think it is worth getting the truth out there so some other hopeful doesn't end up in the same position as you? You're in a unique position where, unlike us, your claims aren't easily dismissed because it is coming from a troll/incel/alt-right/nazi/troon killing forum/whatever else we get labeled as. I mean, when you first came here you were very dismissive of everything we said given the reputation of our website, but imagine if it was some other former campaigner telling you those things instead. It could have saved you a lot of grief, and now you're in a position where you could potentially do that for someone else. It sounds like you've already warned a few people in person, and I'm not saying start a crusade and dedicate the rest of your life to exposing Wu, but it seems like you have a decent audience of local Mass voters you could easily reach through a few FB posts. It doesn't (and arguably shouldn't) have to be something particularly aggressive either, just an honest assessment/warning of what happened to you as a staffer and how you still haven't been paid, despite the fact Wu is now raising funds for 2020 instead of paying off the remaining expenses from the 2018 account.
It's not like you'd even be firing the first shot or betraying a former "employer" since Wu has already insinuated you were part of why her campaign failed, not to mention all the times Wu failed to pay you. Given that Wu is trying (more likely pretending) to recruit staff members for 2020, it seems like now would be a good time to expose the truth, so instead of some hopeful staff member stumbling on KF and dismissing it as a troll site, they'd find posts from someone with a documented history of working for Wu. Obviously the scale is different, but it would be like if Bernie just rolled over and didn't point out how poorly the DNC treated him during the primaries.