Other possibility; a disgruntled investor who poured millions into dead-end fusion research and now wishes they had invested in AI research instead? Blames the professor for persuading them to invest in fusion.
It's a tough one to find a motive for...
Can you quote 1 other example of a disgruntled investor that has killed an American academic over the last 50 years ?
They normally just have their friend the DA lock them up for "fraud"