To answer your question, Microsoft Edge is not currently supported for any releases of the Jive platform.
However, reviewing through your description it appears you are linking to the Jive 8 documentation, so it would not be directly applicable to a Jive Cloud instance. While this is currently in-line with the Jive Cloud platforms, over time it will not be. As such I would suggest the following links for Jive Cloud
Jive-X - Supported Browsers
Jive-N - Supported Browsers