No. Payment is one step in an official process that includes vetting and the issuance of whatever status the program provides; the wire clearing is not an admission. Any move should follow the document that authorizes it, and the terms should be re-checked on the official site before paying.
The bank confirmation is not the immigration decision
The official program describes an online application and nonrefundable processing fee, applicant vetting, a gift request after successful vetting, and then the remaining visa process; a cleared payment does not itself confer admission or permanent resident status. Walt should plan his move around the immigration document he receives, not around a payment date, and should keep his Canadian arrangements in place until then. The official FAQ currently says the process should take weeks but does not promise a fixed completion date, so the household should not rely on a consultant's guarantee.
He should also re-read the official page immediately before payment, because amounts, category and procedure may have changed since he first looked. If he wants an interim way to spend time in the United States, that is a separate visitor question with its own limits.