40 hours have passed, no further response from Doordash on the initial "escalation" reply that promised response within 24 hours.

Googled found this Get Human site

https://gethuman.com/phone-number/DoorDash

No customer service phone number. Only way to contact is thru email with average initial time 30 hours.
Lots and lots of issues reported on the Gethuman site regarding Doordash issues.

Doordash does not even answer the Merchant Support phone number
855-973-1040 - after it is thru, a brief announcement of there would be a 2 min survey after the call - then the phone went silent for the next 15 min till I hang up.

Also found in the Help FAQ - when you encountered issues at the restaurant, the merchant uses a tablet (supplied by Doordash?) then thru the menu to get to the order, tab it to get a telephone number - that can ONLY be called from the restaurant's own phone! No wonder at the restaurant the girl showed me a dark tablet said it was broken therefore she could not contact Doordash but to the restaurant owner, who said he would take care of it. Not.

Such a crappy company.