Fired/project given to another postdoc during F32 fellowship
Generally speaking, it is VERY difficult to fire anyone in academia.  Speaking as a professor with a postdoc of my own, there are generally negotiated contracts between the university and the postdoc.  Faculty and the university can get in trouble if they violate the terms of that.  I highly suggest you talk to your HR person to see if they was all above board.  They will be able to tell you if any of the terms were violated.

Futher, NIH funding, like other pots of government funding, is a contract between the government organization and the institution, not the individual.  That being said, that is frequently overlooked for things like professors leaving one university to go to another and then taking their funding with them.  I would strongly suggest you get a copy of the exact contract between NIH and your institution.  There might be some language in there that can help you.