another scenario
This poses some questions that I cannot answer, so comments from the qualified would be welcome.
Lets assume that the liquid in the wing tanks is a mixture of fuel and ice crystals. This fuel will be warmer than the top surface of the tank during most of the flight. Presumably, the ice crystals, unless they never reach the surface, will sublimate into some water vapor, which will freeze on the colder surfaces of the tank in the form of frost crystals.
Take this tank into warmer air, and the mat of ice crystals will drop off the now-warmer tank top, putting a bunch of snow into the fuel in a short time, possibly enough to overwhelm the jet pumps and clog the boost pump inlet screens at the wrong moment. This could happen to both port and starboard tanks at roughly the same time.
If this abnormal ice crystal load got past the inlet screens, it might migrate
through the boost pumps to the engine plumbing, making the same trouble.
For a greater stretch, substitute fuel vapor for water vapor. I see the problem that waxed fuel would rapidly melt when it fell into the warmer fuel. The water ice wouldn't melt until fuel temp went above 0 C.
These theories could be tested in a lab, or in a real acft with a camera in the tank. The trick would be to find OATs to match the flight in question.
/bill_s