The former. Lukoil was the only energy company in Russia that spoke out against the war. The former President, Alekperov, resigned a week after sanctions were announced. I have no idea where he is currently but you can bet his security are on hyper alert currently.
No one was genuinely supposed to believe this was an accident. It’s a warning shot, aimed at Alekperov and/or any other Oligarchs that have any notions of deposing him.
Long story short is that the Oligarchs collected their wealth in the 90s, following the fall of the Soviet Union and during a period of free-for-all gangster capitalism under Yeltsin. This essentially put them in control of the newly born Russian Federation, although they were loathed within the country. They were a problem for Putin, so he cut a deal with them. They could keep what they had, they just had to bend the proverbial knee and know their place. Abramovich, for example, agreed to this. Berezovsky (you may know the name in regards to Aleksandr Litvinenko) did not. Berezovsky ‘committed suicide’.
Even bought to heel as they were, they still have enormous influence. The western press openly pondered the possibility of the Oligarchs, angry at the sanctions of the seizure of their assets, getting rid of Putin (I suspect this may have been, at least in part, motivation for the sanctions on the first place). If the western press thought it, you can bet your ass Putin did.
Maganov is the tenth ‘mystery death’ of prominent Russian Oligarchs this year, the second from Lukoil. Most have been from Gazprom. He’s cleaning house in regards to the energy sector. It may be that a plot was uncovered, and it may be to send a message to remind them to watch their step. It may be both.