Multisite Copy to New Subdomain w/User Database… or

I have approximately 200 users that I’d like to copy to either a new multisite wp installation (not yet created) or add a new site to the current multisite but with a different subdomain name for that specific site(s). I do not want to have to have the users re-register, or change their passwords or any of that, way to complicated for most of them…… /raises eyebrow

The current Multisite is a WooCommerce conglomeration of several states with their own stores installed for all users to purchase from different chapters around the globe.

I’d like to take all those users and add them to another Multisite or same multisite so I can have them log in and add photos to the galleries from previous, current and future benefit runs and such with their current credentials.

What is my best option for this?
– Create a new Multisite, and backup the eCommerce database and add to new database for photo gallery? (photo gallery not yet installed on current multisite)
– Create a new site and some how change the subdomain name for that site?
– Something else?

I have to get this going right away as all users are eager to post photo from this past weekend’s benefit run. I normally use a phpBB based gallery, but I am growing tired of the style and way that works and always having to have to hard code the updates.

I have full hosting access. (not godaddy or any other bluehost or of the like)

Please help, Thanks.