possibly true as he's not in Canada, but there have been a report of the METV multiple entry tourist visa being issued by either Hanoi or HCMC Vietnam. The METV was applied for.... not the DTV visa.
You may have to show PROOF of your DTV Visa to airline staff on check-in for your flight ✈️ to Thailand...even to the connecting airline staff. Or to the land border crossing entry Thai Immigration Officer.
Upon arrival into Thailand, show the DTV visa to the Thai Immigration Officer and look at the STAMP placed in your passport to be sure you are STAMPED in for 180 days.
Anonymous participant 149 no verifiable Reports of the requirements beyond the initial DTV Visa date and basis of issue. BEST 🚫 NOT to try to do the 180 day extension inside Thailand.