GoblinHokage's journey

I was laid off from my previous role as an administrative assistant at a research firm due to what they claimed was job performance. The reality was much more complicated—I was working with a particularly challenging researcher who had a history of high turnover with assistants. I ended up on a Performance Improvement Plan (PIP) after raising concerns with HR about her behavior, and ultimately, I was let go once the PIP concluded. Up until that point, I had a clean record and had never faced any issues at work. Now, I've landed an interview for a new position, but they want me to sign a Reference Release Form, which makes me anxious. I'm worried that my former employer will disclose that I was fired, even though I plan to explain it as a layoff due to budget cuts, which affected many employees. I'm unsure how to approach this in the interview without coming off as incompetent. I want to be honest but also protect my chances of getting this new job. Should I just be upfront about the situation, or is there a better way to frame it?