Is RD Gateway hosted by Amazon secure enough?

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RD Gateway on AWS—Solution

https://aws.amazon.com/solutions/implementations/rd-gateway

Learn about the solution architecture and details for deploying Remote Desktop Gateway to the AWS Cloud.

RD Gateway on AWS—Solution

My company is about to shift a large workload to a vendor that uses an RD Gateway hosted at Amazon to serve access to the front-end application. It's open to the internet at 443. There's no MFA. How worried should I be?