it was used with the Sea Launch program, Fregat - that's a space tug for Soyuz/Zenit, the modernized Proton-M, ДМ-SL-Б - that's a space tug used with the Zenit launcher.
However the article is a bit old, from 2009. It could have been used for later systems.
https://old.computerra.ru/readitorial/418507/
Wikipedia mentions hybrid variants of Drakon - like Drakon-C, here the they would put C code into each of the boxes of the flowchart (each square box would stand for a basic block, and each diamond box a boolean expression?). I think that would make more sense, this way you could actually write some more complex programs and the flowchart would not blow up in complexity.
https://ru.wikipedia.org/wiki/%D0%94%D0%A0%D0%90%D0%9A%D0%9E...
i guess that with Drakon-C a function call would be just a line in the basic block, would make more sense.