Form 8962 dependent question

CoveredCA (medical insurance marketplace in CA) told me that whether or not our adult children cannot be claimed as our dependent(s), they wanted us to use their combined income with mine on the CoveredCA application to determine what we are eligible for as a household in 2020. This was in addition to of course counting them to be covered by the insurance.

Was it right for us to be asked to use my stepsons' income for their application even though we cannot claim them as dependents in 2020? Also, does this mean we may get more money back?

In the same vain, if we could have claimed my stepsons in 2020, would that have been correct to also use their income in CoveredCA's application, and then use their AGI in our 2020 return in the form 8962 section?

Please let me know with these questions. I appreciate your help.

Thank you