Unsure whether you meant walla, but just in case this is what you meant: It's "voila", from French "et violà".
https://www.collinsdictionary.com/dictionary/french-english/...
They've been around a while, it actually seems quite cool. Bastion hosts are simple to setup, sure, but Teleport adds a whole bunch of porcelain on top, e.g. integration with SSO, web UI for administration, etc.
Haven't used them myself but I wouldn't be against trying it if in the market for something like that.
I find that porcelain has a very bad time in breaking when you least suspect it.
The same is true for server applications that have weird 3rd party dependencies that may go down when you least suspect it.
Not sure what there reverse tunnel product is, but a bastion host is super easy to implement, just spin up an ec2 and walla.
Curious as to what value they are providing