Nope, JulianRoepcke who admits he is no expert, does not understand how physics works.
There's also notwithstanding the fact that, as seen in the longer video clip Roepcke posted, you had people looking up in the sky towards *something* shortly before the explosion happened.
(Plus, Kostyantynivka is in Donetsk Oblast. I guess the Russians shot an explosive into their own territory again.)