As an OINP Job Offer stream nominee myself, I can tell you that Ontario Immigration contacted my employer about confidential financial stuffs. Our CFO authorized our HR to represent him and answered all inquiries by OINP.CRA statements he will not have access to but apart from that other general information which is public should be good. Let’s say I submitted the form with managers information and in case of any issues they might reject the application and not refund money?
Also, refund only happens if OINP returns your application, not reject it.