Correct,
DAN and most others insurance will not cover evacuation if travel is initiated after Pandemic is announced.
Your medical insurance may cover your hospital but all other expenses are on you. So check your medical insurance to make shure at least your hospital bill is covered.
I have purchased a travel medical policy that includes medical evacuation coverage from Blue Cross (GeoBlue Voyager). I called them and went over the evacuation scenarios from COZ to DFW under the current conditions and CDC Travel Warnings and they assured me I will be covered. They informed me that IF the CDC/ Dept of State issues an evacuation order from Mexico after I have arrived, I would need to comply and leave Cozumel ASAP or risk denial of any claims. The written policy and exclusion of coverage also support what they told me. It was relatively cheap too. Zero deductible. $1M medical limit. $500k Medical Evacuations to my departure city (DFW) .
They did tell me that the policies are reviewed almost daily and subject to change. My policy, as written, will be honored though.