TD does not authorize work; an agency placement needs its own lawful authorization.
Separate placement from permission
A recruitment relationship or a conditional offer may exist before employment is permitted. The spouse should not begin customer assignments on the strength of the principal’s TN evidence.
Treat the principal's TN request and the spouse's proposed agency placement as two separate files, not one shared arrangement. Confirm each person's citizenship, intended activity, start date, and actual employer; Canadian permanent residence must never be recorded as citizenship. The principal must independently hold Canadian or Mexican citizenship, credentials matching a listed USMCA profession, and prearranged professional work that excludes self-employment. TD status permits study but carries no employment authorization of its own, so an agency contract, payroll setup, unpaid trial, or mere customer access does not let the spouse work. Before any productive task begins, the spouse needs a distinct immigration classification that itself carries employment authorization; a recruiter willing to place both spouses cannot substitute for that requirement. The Canadian principal separately selects the appropriate port-of-entry presentation or Form I-129 filing sequence.
Hypothetical example: a North Hatley forester plans TN work assessing timber health, and her husband is offered bookkeeping shifts by the same recruiter. The couple should gather marriage and citizenship records to support his TD status, but keep his job offer outside her TN evidence. Entering customer invoices, reconciling accounts, or training on live files would be work even if performed remotely from temporary housing. He may accompany her in TD and decline those duties, or pursue a separately authorized status permitting his actual job before accepting the placement.