Maybe. Assuming this is a US card, “Inclement weather, which prevents a reasonable and prudent person from traveling or continuing on a Covered Trip” is a Covered Loss. However, note that Amex’s policy specifically excludes “One-way travel that does not have a return destination.”

https://www.americanexpress.com/content/dam/amex/us/credit-cards/features-benefits/policies/pdf/Trip_Cancellation_and_Interruption_Insurance.pdf

really though this seems like emirates’s responsibility not Amex’s, and they really blew it on re-accommodation (not that they’d be expected to provide a hotel, but I’m surprised they wouldn’t provide a new connection onward from Dubai; perhaps an issue of not being able to stay in Dubai due to covid or visa restrictions?)