Can I invite a VA to company accounts / why can't I invite a VA to company accounts?

The simple answer is NO you cannot invite a VA to a company account.

Company accounts are only for the employer or managers of your company. Company accounts are specifically designed to cater to employers and managers who need to hire and pay VAs in different jobs in different workspaces (departments ). Unless you promote a VA into a managerial position, Company Accounts are only for Employers and Managers.