well if you keep it in a velvet bag I’m sure it will last but highly unlikely they will even ask as they already know from your tdac approval to enter the country,that you have a DTV just hand the passport over to the IO and await the coveted and exclusive DTV stamp🤷🏾♀️
What is your nationality, after submitting your application did they request any further documentation, or how soon did you get rejected from the date of submission?
so how come he says 7 days, thst is just not enough time, even 10 working days might be tight. Allow 2 weeks, enjoy HCMC everything is incredibly cheap there!