The License Usage page, found within the Licenses drop-down in the Solution Manager, will show statistics related to licenses which are being used. Since your server is not starting, it makes sense that it has not shown up in the License Usages page yet.
If the Staging environment is new, you will need to create a new environment within Solution Manager. Then add a new cluster, and finally, the node representing the staging VDP Server with its IP address. Once that has been done, then the staging server should be able to start and pull its license from the license server. After that, you may check the License Usage page to see its usage.
In the event that you have already added the new staging server as a node to the Solution Manager, it’s possible that there was an unexpected restart and the license manager may not have released a license. In that case, here is a link that may help:
Hope this helps.