Unfortunately, we have multiple forms that don't apply to all customers and we would like to restrict certain forms to specific organizations. I have seen articles with steps to accomplish this but it is not supported by Zendesk and you need to input custom code.

Not sure if the tag is the best way to achieve this, but there should be an option, such as when creating a Macro or a Form, where you can select to what organizations it applies to.

Another option can be to create a Contextual Workspace for customers, similar to the one we have for agents