For starters, I'm aware of the concerns generally brought up by many when someone looks for a way to skip duplicate e-mail checks for creating new user accounts.
However, In my case, I believe the reason for needing this is justified if I can explain it.
I'm building an extensive vendor directory on my site using a membership plugin with public member directory (Ultimate Member). The problem is, Not all vendors are to register an account on their own. There are vendors I'd like to include in our directory purely for their public contact info for other users to search from the directory.
For these vendors whom we can categorize as (unmanaged vendors), I'd like to use some catch-all e-mail such as email@example.com to register multiple accounts. These accounts will never be logged into, thus making issues with password recovery not an issue. I also cannot create a new e-mail address every single time to add each of these unmanaged vendors, nor can I just use fake e-mail addresses each time due to email bounces.
Up until last week, I was using this plugin called "Multiple Accounts" to allow only a specifically designated e-mail address to be allowed multiple registration.
However, I've moved my site to Multisite, and this plugin seemed to have stopped working.
Upon web search, I've seen some function snippets people have suggested to bypass e-mail checks, but for reasons frowned upon by many, I cannot simply allow any and all e-mails to bypass this. I'd like to create a bypass for only 1 e-mail address (e.g. firstname.lastname@example.org).
Would this be doable with a snippet for multisite install?
By coding logic, I'm thinking along the lines of If registration email is email@example.com, then allow registration without email duplicate check. All Else standard registration.
I'd appreciate anyone to shed some light into this. Thanks in advance!