Red Persian plum?

I had a friend ask me to look at their plum tree because it doesn’t fruit. 4 years in ground, they are debating on whether or not to remove it.

Nice looking tree, the tag said Red Persian Plum. Anyone know what that is? Never heard of it around here in southern Califirnia.

F,B&N Inventory 4th Edition says the following…
Persian, Red - Medium size fruit. Red skin. Dark yellow, crisp flesh. Heavy bearer. Ripens August to September. 350-450 chill hours. Source History: 1 in 2009. Sources:ORA

ORA is
Orange County Nursery, Inc.,
5485 Grimes Canyon Road
Moorpark, CA. 93021
Wholesale only!

Plums of North America says nothing about Persian, Red. Only Persian, Green.