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 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.
Definitely battlefield experience and battle testing their weapons. No one wants to end up in a war and find out that their guns don’t work, their missiles are inaccurate and their air defence can’t intercept anything. It’s the same reason Iran is sending their new domestically made anti ballistic missile defence systems to Russia for use in the war. They want to test them in real combat, and improve on any flaws.
A lot of the escalation between the DPRK and ROK was because of the now impeached ROK president and the Biden administration exempting the ROK from certain arms treaties, so the situation should calm down for now. But it will heat up again, maybe very soon. So it’s always best to be prepared.