I think you're going to need to be strategic with your signals to be successful. Failing a clerkship is often a big problem. It's perhaps a bit better if your clinical performance was fine but you fail the shelf, but it sounds like you actually failed the clinical portion of peds. If you were "going through some stuff" that impacted your performance you should have taken an LOA or some other solution, but it's too late for that.
I think your chances at "T20" programs is very low. Top programs look at top candidates, which you are not. You only have a limited number of signals, and I think you needs to seriously consider focusing them on community or less competitive programs. Feel free to apply to T20 programs without a signal and hope for the best -- worst case scenario there is just wasted money. Probably also focus on Midwest, which will be less competitive (in general) than West Coast.
You definitely need a mentor to help you through this. Also, you may want to consider some targeted SubI's at programs that would be a reasonable option for you. Your S2 score may also help target programs.
And last, you need a backup plan. Either to apply to a backup specialty, a SOAP plan, and/or a gap year plan.