Career Advice - MBA or lateral?

Hi all - been grappling with some challenging personal circumstances / career setbacks and wanted to get some advice from the forum.

Background on me: 27M, graduate of a state school (UCLA), and ~4 years of work experience across a small PE firm, a MM investment bank, and most recently a corporate development and strategy role at a middle market consumer company. 

I won't bore people with the specifics but I've faced a number of pretty tough set backs over the past few years that I feel have derailed my desired career path. I lost my original FT offer to COVID, was fired from the backup PE job after ~2 years after we failed to raise a new fund, went into a  depressive episode and developed panic disorder after ending up in a rebound banking job with a very challenging work environment, and then took my current role out of desperation to get out of the toxic workplace environment in IB.

Speaking bluntly, my current role is a complete joke for what was supposed to be a deal-focused role - instead of m&a, I spend most of my time doing project management-type work for board presentations or miscellaneous IR workstreams (i.e., tracking and reporting competitor performance). I've been trying to find a new job that's a hybrid corp dev / venture role for a while, but have not gotten much traction to-date. 

In summary, my career (if it can even be called that) has really struggled from the start, and I'm having a hard time moving my life in a positive direction. I'd love to make my way back to a deal / private markets role in some capacity - either at a large corporate that has a real M&A function or a growth / early stage fund - but it seems like the path to those roles requires pedigree and the 2+2 resume that I just don't have. 

Some folks in my network have suggested that I should consider going back to IB to get back in the recruiting pipeline, but I had a very negative experience at my prior bank and am hesitant to take that path unless there are no other options.

Is business school my most viable way forward here? I have a decent undergrad track record with a strong GPA, I'm just concerned that my spotty work experience will preclude me from getting into a school that would make the $200k+ cost worth it. I also feel like most of these coveted corp dev / venture roles want pre-MBA experience, and an MBA by itself isn't really sufficient to jump to an M&A role at an active corporate without strong prior experience.

Appreciate any advice from users who navigated the corporate development path with/without business school. Thanks all.