Installing graylog with docker - Problems in Requirements

Hello out there,

I want to install the graylog landscape using docker (kubernetes) in graylog version 6.0.x
The requirement page showed out, that I do not install / upgrade to opensearch 2.14, which for me implements, that opensearch 2.13 is the least supported version.
Docker Installation (graylog.org)
As shown out on the opensearch project documentation it looks like, that opensearch 2.14 is not within the opensearch support range and I had to install opensearch 2.15
Docker - OpenSearch Documentation

I am a little bit confused …
Can anyone help me out?

Kind regards