I stumbled on this place by chance (at time of writing the map marker is pointing to the incorrect place I 've just submitted a request for that to be corrected). It has a big front right on the corner and so is easy to spot.
I showed the waitress a Vietnamese text and pictorial representation of what vegan means. She replied indicating there's no egg, dairy nor honey added used in preparing the food. Whether though that also includes the mock meats, you need someone with better grasp of Vietnamese than me to ask. There is still though an abundace of dishes without mock meat to choose from for those who prefer.
There's a whole bunch of food laid out in the counter. Me and my co diner thought the food was inexpensive and tasty. we've just filled up for lunch for 138 000 dong. Your dong seems to go a long way in that place.