Totally agree Only thing to add is for the U.S. its pretty easy to spin up a bunch of numbers so generally this will work only for a while. On the latter they are farming you for information Just confirming who you are is a mistake IMHO
First off sorry you are in this situation it sucks. I have mentored quite a few people thru this situation and here are my thoughts. If you can afford it a lawyer is a good idea. It doesn't hurt your relationship with your other founders. They clearly consulted lawyers before letting you go which is why they are asking you for a release. On the other hand don't just use the lawyers to communicate with the other founders but do use them to understand your rights and your situation. Your co-founders should respect you even more if you stand up for what you believe in and what you are owed. It may be painful in the short term but generally I find people respect those who stand up for themselves. If they are asking for a release you have leverage and I don't think it is a big stretch to ask for your 12 months. One thing to discuss with lawyers is what were the terms of your offer letter. Was their acceleration? Are they trying to terminate you for cause? If so this is really hard to prove in California and its unlikely they would try to do so.
Finally on the expenses if you have the receipts submit them its another item in your favor.
In the end there is often a lot more to these stories than it seems so I am sure there is a lot more going on, but if you keep a cool head and focus on getting to something that is fair you can close this chapter and move on to your next with the knowledge that you got what you deserved and learned some valuable lessons