The Russians have not yet been able to produce any of the thirteen and get them on camera
But considering the shambolic way the Russian’s are running their invasion, it may just be that they have lost them.
I heard something like they produced a total of 80 prisoners from that part of the war, but even so, who knows.
And one of the problems is that the language and ethnic makeup of Ukrainians and Russians is virtually identical...so we’re pretty much left with joint statements as about the only thing that may be trustworthy.