Your answer is incomplete. They are either independent or employee, and depending on the IC vs. EE rules is how it works, not in order to save money. You must comply with one rule or the other. <<(S Corp) under my FEIN, and EFIN numbers and tax software >> is irrelevant, but the << business insurance>> is very problematic.

If IC, you cannot pay their insurance, and you must inform your clients that they do not work for you. You are giving out private information to third parties and that is dangerous.

<<They bring their own clients to my company. I review at the final.>> Maybe they are ICs. Do they pay you for the review of THEIR CLIENTS' RETURNS?