Russia has been using DPRK military equipment for over a year now. First Hwasong-11A (Mars Type-11A in English, KN-23 NATO designation) ballistic missile attack was in January last year. DPRK military equipment, including howitzers (in the Koksan M1989 “Juche Cannon”), tactical ballistic missiles (in the Pukguksong-2/Polaris-2/KN-15), and air defence systems (in the Tor-NK) have been spotted in rail transit within Russia since November last year, and spotted in combat positions (presumably in Kursk) in the last few days.
I don’t think it’s a stretch to say that North Korean troops are in Kursk, I’d say that it’s likely at this point. Are Russians operating all of this equipment on their own? I’d find that unlikely given that the equipment (aside from the KN-23 missiles) was first spotted in November - December of last year. You don’t need any POW videos or Ukrainian gore videos of Korean or East Asian looking dead troops to come to the conclusion that there are DPRK troops in Kursk. There’s enough evidence otherwise. The response to the ridiculous Ukrainian propaganda about how North Korean hordes are overrunning Ukraine and dying in their thousands should not be to deny the situation completely, it should be to try uncover the truth of the situation.
Obviously this POW interview does not hold any value, they never do for any side in any war as there is always influence by the interrogators, torture, incentives, etc. The only interesting thing here is that the POW appears to be speaking Korean in an unique accent. I don’t see how that would be possible if the POW was Russian.
There was more evidence aside from that, even if you ignored all of that Ukrainian propaganda (which you should) there was still lots of evidence of participation by the DPRK in the war.
See my comment here