The fingerprints of Western intelligence agencies are ALL OVER this death.
There are no coincidences when it comes to these people.
They didn't because they know it would give the West a propaganda win.
So, yes, it's very likely he either died of legitimate medical condition or because of the work of the CIA or MI6 or the equivalent. They probably found a pro-Ukrainian Russian willing to kill him.
The timing is way too convenient with the Senate bill being endangered in the House and with the fall of Avdeevka, which is total disaster for the Ukraine military.