Stay uninsured or get temporary insurance?

I got laid off from work a few months ago. I didn’t know you only have about 1-2 months to apply for health insurance through ACA/marketplace for a QLE and missed the deadline to apply. I was overseas for a while and figured I would just apply when I returned to the states. Now I have to wait until open enrollment and my coverage won’t start till January unless I manage to get a new job before then.

Now I really need to see a doctor. I think I either strained a muscle, pinched a nerve, or have a herniated disk in my lower back.. I don’t want to risk permanent damage by going without treatment so Id rather get checked out now. I’m not sure if I should get temporary insurance or just go to the non-profit hospital near me.

The best plan I found is though United Healthcare with a 2500 deductible, 300 a month, 0 coinsurance. Of course pre-existing conditions aren’t covered, so I would have to fib a little about when my injury and symptoms started. But I’ve read reviews about how these plans are basically scams that will do anything to avoid paying. They might refuse to cover costs on technicalities and I’ll be out even more money by buying their insurance. But if they do cover everything the most i would pay is like about 3500 for treatment.

The other option is go to my local non-profit hospital. I know they reduce the bill for those uninsured or who can’t pay, but even afterwards people are still billed thousands of dollars. Should i just make an appointment with my pcp or my neurologist instead and pay in cash? Is urgent care a good cheap option and will they have the diagnostic equipment i need?