The transcript for the engineering degree, the provincial permit if relied upon, proof of citizenship, and a draft of the U.S. entity's letter to compare against the internal transfer memo. Resolve any conflict between the two before either is finalized.
How to sequence the paperwork
Start with what only the applicant can produce: the transcript, the permit card, the passport and a résumé that lists employers by legal name and date. Ask the university registrar for a sealed transcript now, because that request has the longest lead time. Then obtain the draft U.S.
letter and read it against the plant's internal memo line by line, noting duties, pay, duration and who signs. Any statement in the letter that the applicant cannot personally verify, such as a claim about her supervisory authority, should be corrected before signature rather than explained at a port of entry. If the Québec employer will remain the paying entity, add the intercompany services agreement so the officer can see the U.S.
entity has actually arranged her work. Keep a dated index of every version; the version presented must be the current one, and superseded drafts should not travel with it.