They could disclose that financial information with an NDA at minimal risk to themselves. They could even choose to leave out sensitive details.
They are being cagey about equity because they want to stiff you on it, or at least, that’s what you have to assume.
If there’s no VC involved I think you want to know the owners’ goals and you want to evaluate whether this company is going to scale or whether it’s functioning more like a small business.