It says you don't have to collect the income data, but if you do, report what was considered. Based on the question the bank uses personal income. That would be reported.
You also indicate the bank will "rarely use gross revenues of the business..." This is questionable if there is not a well defined guide for when the business income is used. This could be an ECOA issue as part-time income as one example can't be excluded just because it is part-time income. This can be discriminatory.
Back to the question, if you collect it, report it. And you report that on which the decision is based.