Create an indexing subgroup • FamilySearch
https://www.familysearch.org/help/helpcenter/article/how-do-i-create-an-indexing-subgroupIn Web Indexing, you can create a subgroup within an already existing indexing group.
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It looks like you need to send them an email using their family search contact name? I found that info at the bottom of this link I'm sending you where it says "next steps."
I hope this helps!