Formula URL or Webhook command to deactivate user

Due to the nature of our project, we had to setup a custom table with a user as the key in it. This is to enable some additional access permissions to different tables. 
One issue that we have come up with is that now we have to have a bigger process to create  a user and subsequently deactivate them (can never delete them probably). 
I am trying to consolidate all of this within the custom table and can easily add a new user now but am also trying to provide a button to deactivate the user. 
It can either be a button or i can also execute a custom action (or webhook) when the user is marked as inactive in my custom table. 

Please help.