Lawful employment requires an authorization that exists in its own right — a status permitting the work, or an employment authorization document granted through an eligible process. Neither a pending investor petition nor an approved one supplies that. Ask counsel to name the specific authorization, when it could be applied for, and what conditions attach to it.
Ask for the authorization, stage by stage
Request a short written table from counsel: each stage of the case, and for every family member, whether work is permitted at that point and on what basis. Blank cells are the plan's real content, because they show the months in which income must come from elsewhere. Revisit the table if the route changes or if the spouse receives an offer that assumes an earlier start.
An employer's expectation cannot create authorization that has not been granted. It is worth being explicit about the two things people most often confuse. A receipt notice records that a filing was made; an approval records that a petition was granted.
Neither is a status, and neither authorises employment. Lawful work requires either a status that permits it or an employment authorization document issued through a process the person is eligible for, and eligibility for that process depends on where the family is and what they already hold. Ask counsel to name the specific instrument, the earliest date it could be applied for, and what would make the application premature, since a filing made too early is money spent and time lost.