AWS DX to AWS DX via 3rd party Layer 2 VPLS

Is it possible to BGP peer DX VIF's across regions, without a dedicated (customer) BGP router?

We only have infrastructure in the Cloud, we could spin up a network appliance in the VPC, but it seems like we need something directly on the other end of DX/VPLS for this.

This is pretty much the same question as https://forums.aws.amazon.com/click.jspa?searchID=12352637&messageID=814856 raised 2 years ago, just hoping ideas had changed since then.

Any direction would be greatly appreciated.

Thanks