OOC: this one is pretty tough. East Germany is SURROUNDED by by NATO states post-fall (North Korea actually has a small, easily fortifiable border of about 120 miles with the ROK). That’s a lot of ground to lock down. I also can’t see how it’s in Russia’s interests to aid this DPRK with white people (and where on earth are they getting the money to support this puppet state). In fact it actually significantly hurts them because there’s no way the west would provide the economic aid that kept them barely alive in the 1990s if they extended such a big middle finger. Wouldn’t surprise if Russia ended up as a failed state if they tried this. I also can’t see Russia ever being kosher with aggressive Germans with nukes. Even IOTL they seriously didn’t like or trust the DDR, and worse still when the two Germanies reunify like they probably will there’s a very good chance the new state would keep the weapons if Russia made such a clear statement of hostile intent. That makes it very difficult for me to see an opening for them to start up a nuclear program.
I do try, however, to not just shoot down ideas, so let’s try and make this work. We can compare the the DDR IOTL to the DPRK but the better template would be Hoxha’s Albania: an extremely isolationist, anti-foreign power that just wants everyone else to stay the eff out. The DDR can’t be like North Korea and adopt a seriously aggressive posture against the rest of Germany or anyone else. The mere idea of them as a military threat is a joke given how small they are and how every country around them plus all other NATO members and the organization’s nuclear umbrella will auto-attack if they try anything.
As for their nukes, let’s say things in the USSR unravel a bit quicker, there’s a botched coup that Gorbachev narrowly wins in 1988-89. We can say the POD is that the Shah doesn’t discover his cancer as quickly (first diagnosed in 1974 IOTL, let’s say 1975 IATL) and dies in late 1977 before he can go full potato and order the publishing of the anti-Khomeini article in the state newspaper. The Iranian Revolution is butterflied, and with it the 1979 oil crisis. This costs the Soviet economy a few extra years, and things fall apart before the question of the DDR can be resolved. With the Soviet Union going to pot and the armed forces disintegrating, the Stasi sees the writing on the wall and quietly secured a couple dozen of the many nuclear warheads stored by Group of Soviet Forces in Germany, saying they are “safekeeping the weapons of the Communist party until the present crisis has passed.” With Moscow in November 1991 level dysfunction and crisis, no one is able to stop them. The USSR falls, and the East Germans expel all the former Soviet troops who they denounce now as counterrevolutionaries. They keep the nukes they took and a lot of chem and conventional ones, then declare martial law, kill anyone who makes discontented noises, and go full isolationist as the economy free falls and desperate poverty becomes widespread.
Oh, and as for how the DPRK reunites with the ROK, let’s just say the 1995 coup attempt when the Ground Force’s 6th Corps tried to march on Pyongyang is preceded by a raid that kills Kim Jong-il and the other major head honchos and the whole regime disintegrates.
There we go. Sound good/can we agree on a common plausible point of reference?