Request invite to closed web app – what information to ask for?

Our site is a closed service where users request an invitation to access the site. We are primarily looking for producers and makers to join to share information about their products, stories & track the supply chain of their products.

In this request form we ask for their first/last name, company name and the service we offer requires users to associate with being a 'brand', a 'producer', a shopper' etc.

This would then be filled in, sent to us to review & we would immediately approve this user if they seem to fit the profile for people we're looking for to join our app*.

Or we would follow up via email and ask for more information from them such as their website url and their social media profile links plus a short explanation of why they'd like to join our platform.

I'm putting the case forward that asking for the information of their company website and why they'd like to join upfront will require less manual back end work from us. I do, however, appreciate that users may spend less time initially filling this information out & would perhaps spend more time on it after a follow up communication.

Is there best practice for verifying a business account in this way: is the information we're asking for even correct or should we approach in a very different manner?

*Disclaimer: Our site was open but we work with blockchain so lots of people signed up to a free account to try & assess our blockchain so we have thousands of empty/uncompleted/inactive accounts. This sign up is to address this issue & have active/engaged users.