CIA and IB (Indian Intelligence) lost such Plutonium RTG powered listening device at a Himalayan peak in 1965 used for SIGINT against China. Further expeditions to retrieve the device resulted in failure and later they installed another such device in 1967[1] which was supposedly taken out in 1968.
[1]https://www.livemint.com/Leisure/3QfYqLadggrbnrn41H0mAJ/The-...
Looking into this, it needs a simple control system. The PU-238 bricks just made heat continuously with no control. But, they were also much less power.
If there's a control system you can launch the reactor cold. With the Plutonium bricks you cannot, meaning your cooling system (engine in this case) has to keep running during launch.
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200900...
I don't think there was any way to save and restart anything if an engine failed as it would have likely destroyed the engine.
https://rps.nasa.gov/system/downloadable_items/36_APP_ASRG_F...
(2) Cooling. Space is hot. (+400c)
(3) Running the computer.
(4) Running the communications gear.
(5) Cooling 4+5.
https://en.wikipedia.org/wiki/External_Active_Thermal_Contro...
Nobody knows what kind of innovations a huge readily available sustainable energy supply would allow, but I bet they'd be cool.
[1] https://englishrussia.com/2009/01/06/abandoned-russian-polar...
Yet on the other hand we can't even keep a country stable for more than a few decades. The soviet union fell into disarray that time leading to all kinds of incidents, and we had a major world war only 75 years ago which is nothing on nuclear waste time scales.
One way or another this will bite humanity in the back in the future. If it isn't by a malicious future actor weaponising it, it'll be by neglected nuclear waste storage facilities that last much shorter than the waste itself.
For another example of things that can happen see https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident . That one was medical in origin but the same can happen to nuclear waste when not adequately protected of which there is a lot more.
It is not potentially misleading. This is just you being pedantic about a connection that very few people make. When you say "nuclear power plant", people tend to think of nuclear fission reactors, not RTGs or fusion reactors. Both of these are applicable to the term "nuclear power plant", but only one is commonly referred to by the term. A lot more people would feel misled if it actually referred to RTGs when it said "nuclear power plant."
The only group that it could potentially mislead is people who know RTGs exist. Most of those people would instead think "I wonder what kind of nuclear power plant it is" instead of "wow, what a misleading headline!" unless they were intending to be pedantic (like you).
Which makes the main danger that the Plutonium may get into the wrong hands.
* Happy to learn if that's wrong :)
The casing on RTGs have typically been designed to survive reentry. One example is Nimbus B - the rocket failed late in flight. The RTG was recovered from the ocean, refurbished, and flown again on Nimbus 3.
You could potentially make a dirty bomb out of one. Just a conventional warhead that sprays radioactive fallout.
In order to get approval to launch nuclear material, the launch vehicle must be nuclear-rated (like human-rating, it ensures safety). With the recent retirement of the Delta II, only the Atlas V is currently nuclear-rated, but eventually others may be. Additionally, the fuel is encased in boxes designed to withstand launch failure and impact into the ocean without releasing the contents.
In the case of RTGs, the fuel is always releasing heat and is always radioactive. For fission reactors, the fuel is relatively inert and non-radioactive until it is turned on.