First of all, you asked a similar question in May and were directed to the Turbo Tax Community, because this is a personal tax issue and you are posting in the ProConnect Tax user community, but don't seem to have a "using ProConnect" question here.

Second, as with that prior topic, you seem to forget you ask about the LLC, then turn it into "two individuals operating independently from the LLC" and you should use the same reference materials for yourself that you would use for taxpayer clients, because that is the stuff you are supposed to be up to speed on, as an income tax preparer professional.

Third, you don't have "401k plans." Businesses have a 401(k) plan. The people that are covered under that plan do what the plan provided.

As proof of your confusion: "and not in the name of a state law entity (including a limited partnership or limited liability company)"

So, once again, you are not asking the right interwebs community.