Hi,
I figured you archived the repo rooot
Composer now indicates it’s no longer maintained. Is there a new way to make multisite work on Bedrock without it?
Thanks!
The plugin still works and can be installed. It’s read-only because the repo has not been maintained.
At this point the plugin should be forked if someone is interested in fixing the outstanding issues 
You might look at the network, there are already a few forks that are ahead of the roots master.
Not sure if those are fixes for any of the issues or just updates that were made, but ouun looks like they’ve done the most.