Is the fit to fly certificate from Quick MD legitimate for entry into Thailand?

Not a scam great system. I used it once for something else.

Informal medical certificate in English that you are fit to fly (also called “Fit to fly / Fit to travel” medical certificate), issued no more than 72 hours before departure

Medical certificate in English certifying that you are free from Coronavirus COVID-19, together with a laboratory test using RT-PCR, issued no older than 72 hours before departure

It’s not a scam and the time for the medical will probably depend on the doctor used.

If the doctor knows the patient.. then it is only a formality. The time it takes to fill in the form and sign it.

If the doctor needs to do a medical checkup before signing the form. Then all can be done in two days.

A scam it is not.

You just need to get the timing right for the not older than 72 hr. Part.

That should not be a problem.

have read several who have.