They have lost a vast number of troops, and have been having trouble recruiting more. There are still plenty of people available, but they mostly wanted to recruit prisoners and others that nobody would really miss. Going to North Korea can be read as an admission that they are running out of options.
As you say, it's not that many people. It won't change the situation on the ground. It just preserves the status quo, temporarily.
Which is all that's needed. The US is having an election which could have enormous consequences. There is a serious possibility that the US could cease to give aid to Ukraine, dramatically altering the balance of power.
If that doesn't happen, the outcome is murkier. It may be that they use the North Korean troops to give the best bargaining position for negotiation. Or they may fight until the new troops are gone, and then find more from somewhere.
Either way, it's a significant development, even though it does not in itself change the situation on the ground right now.
https://www.armscontrol.org/act/2024-07/news/north-korea-rus...
That's also why North Korea bargained some goods in exchange of their support.
> they didn't have a military alliance.
Please just admit you were wrong. If you cannot do that then there is no point in responding to you.
Maybe you can point at some pre-existing defense pact to support your claims signed before the war but I'm not aware of any existing.
It's possible that I missed it though but given that Putin flew in there when the situation got worse to negotiate their war support, I doubt they had one.
That help is coming in form of both armaments and training such as the AFU members training in France. All that with our taxes and without popular consultation...
I'd even say Russia just gave the green light for EU countries to replicate what Russia just did, they opened up the debate.
It makes no sense for you to write all of this argument and not consider this simple latter point, an aggressor force wanting to annex sections of a different country is getting help from a 3rd party outsider to even deploy troops.
Trying to fake a play as "both sides" is underhanded and shows quite well how immoral you are.