I really don't see how this can plausibly be anything other than intentional. Shutting off these fuel switches as a mistake would be like turning off your car and putting the keys in your pocket instead of shifting. The switches could have failed, but both switches failing with a 1 second gap between them is incredibly unlikely, especially with the way they were designed. I also doubt it's a software issue where the state of the fuel pumps became disassociated from the state of the switches based on how the report mentions the switches themselves transitioning.
Edit: upon thinking about this more, I don't think accidentally turning off the switches is impossible, but it still seems too egregious of a mistake to be likely. In terms of a mechanical failure,I wonder if fuel flow ceased due to another issue and the crew had to toggle thrust. That also seems unlikely to me as the report mentions the transition of the switch state before power loss.