The sudden onset of the problem does make it feel like an ignition problem to me.
A weak or intermittent spark could cause a lot of this I think.
Do you have a timing light? Hooking one up to each spark lead in turn will let you observe if that plug is firing evenly, or intermittently, or not at all.
It might be worthwhile to take a blow dryer and warm up the points area, and also inside the headlight bucket, and the wiring under the left side cover, to try to drive off any water.
While you're poking around in the wiring, take one of the bullet connectors apart and look at the ends, are they bright brass colored, or grungy looking? If the connectors are corroded then that can cause all sorts of problems. Clean them up with a scotchbrite pad if necessary.
Try running the bike at night and see if you can spot any arcing from the plug wires or down at the plugs themselves.
I've ridden in the rain with pods, sometimes in pretty heavy downpours, and while the bike sometime ran less well, it never outright died on me.
Sudden shutdowns like that do tend to be electrical, unless they're mechanical, but if you'd thrown a rod you'd have noticed this by now
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mystic_1