There's a lot of weird stuff here:

It says they filed a request under the "Freedom of Information Act on Mar 6th 2018 including requesting the ATC recordings pertinent to the arrival of that particular flight NK-708 on Jul 17th 2015 into Boston as well as any filings made about the occurrence, on Mar 12th 2018 we received the reply"

6 days, two of which are weekends, to send and receive a reply? Even if they had a proxy physically in D.C. I find that implausible speed for the FAA. Yet Aviation Herald is based in Austria so where was the request send from, and where was the answer received, and can we see both request and reply? Why not include them in the article? FOIA requests and their answers are very specific, we should be able to read those documents not just have fairly confusing and inexact summaries of what they contain.
http://avherald.com/h?impressum=&opt=0

"Neither NASA, FAA nor NTSB databases have the event listed."

Unremarkable if neither pilot immediately filed an incident report with the NTSB as required by regulation. What is remarkable is that they didn't file the required incident report. But even to cover their asses, they didn't file an anonymous ASRS report? That's just fucked up. The ASRS reporting system is handled by NASA, so I assume that's what Aviation Herald is referring to by reference to NASA: no ASRS reports by the pilots. That's weird.

I start losing consciousness, and my fellow pilot totally loses consciousness, we both need to don oxygen masks, and neither of us can remember landing the plane - as a pilot, the very idea that anyone on the ground prevents me from filing an NTSB report about this? Beyond ridiculous. Ridiculous meaning, worthy of ridicule (if not a moral imperative).

Being intimidated into violating regulations is a completely foreign concept to me. I sooner expect to be assaulted, and to commit assault in retaliation, on my way to the phone to call the NTSB to make the required report! Call the police while you pinch off your bleeding nose, and I go call the NTSB. I have zero patience for this kind of chickenshit nonsense. And any pilot who participates in it, is actually this easily intimidated after having just escaped death, who won't even bother to make an anonymous ASRS report? Appalling. Disgusting. Bizarre. I have no explanation for it.

And then you'd want to call a union rep, or a trade rep, and get or hire an aviation attorney within that same week. They would double check that the NTSB had the incident report and get a copy. They'd make sure to get all medical records from every person and facility you've seen for these symptoms. This is very serious business.

Which means no matter what you believe about the report, you have to take the reporting seriously: it is either a serious libel, that Spirit airlines violates regulations and by intimidating pilots to also violate them is probably committing crimes; or it's an incredible misfeasance, shut down the airline. If true, there's no telling what sort of records the airline has corrupted if they're willing to do what is claimed in the article. Shut down the airline. Full audit of all record keeping, maintenance records, one on one interviews with crew, company officers. This is NTSB, FBI, and maybe even FTC. How exposed to this liability are the board of directors?