An employer/employee relationship is that of master and servant. An FI, self employed if he is a CPL or a volunteer if he is a PPL, registered with and working through a training organisation is not a servant of that organisation.
He is however an agent when working within the scope of his authority.
The fact that payment is, or is not, made to an FI is not relevant to his status as either a servant/employee on the one hand or a mere agent on the other. It is a matter of contract between the parties involved.
Does that help Slopey?