The repo contains a single script which can be run from the command line in the AWS SSM console to create a temporary local admin account.
Run the command:
## set TLS for windows ps session
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
## command to start interactive temporary rdp user
iex $(iwr 'https://raw.githubusercontent.com/grolston/SsmTempRdpUser/master/SsmTempRdpUser.ps1' -UseBasicParsing).Content