That documentation applies to our virtual appliances. For hyperv and esxi. To extend a local network to AWS using the AWS VPN gateway service.
Our AWS images are already on AWS, and AWS has VPC peering, so there's really no point doing that.
I would suggest you use site-to-site using openvpn itself and ignore ipsec. See this page;
https://openvpn.net/vpn-server-resources/site-to-site-routing-explained-in-detail/