I think Jones was scared of Ngannou. Kinda like how Floyd didn't want none of Pacquiao in his prime, but worse, because Ngannou literally has what it takes to have beaten Jones in Reyes, but much, much better, whereas prime Floyd vs prime Pacquiao, you still probably favour Mayweather.
Now, Jones is ducking Aspinall, but I don't think Aspinall hits as hard as Ngannou nor as good as Ngannou. I don't think Jones is scared of Aspinall, I just don't think he's that confident of his chances. I think Ngannou wipes prime Jones, and Jones is far removed from that. I think Aspinall probably beats Jones, but I wouldn't be hundred percent sure. I do think so.
I don't think Rumble ever had what it takes to beat Jones, may he rest in peace though. Rumble was a beast...
So I'd say in terms of him ducking
USADA
Ngannou
Aspinall