A crude analysis of the effect of wavelength on the RasPi Xe flash problem:
I thought the higher frequency light emitted would be the culprit, but a 5mW 405nm (deep violet) laser did not affect the chip at various angles or focus ranges including a pinpoint dot.
However, a 110mW 532nm (green) laser, even at wide focus ranges (lower intensities) consistently caused the Raspberry Pi failure.
My next thought was that since 532nm lasers are frequency doubled in a crystal from a 1064nm (IR) diode, there could be IR leaking through and causing the effect. I had the output analyzed and found less than 5mW in the IR region which should not affect the chip at the very wide focus because it is about as intense as a typical IR LED. I then tried using a remote with an IR LED and confirmed that the IR in the laser was not the cause.
Also tried were: blacklight, 650nm (red) 1mW laser pointer, and xenon strobe though a >99% UV filter. The blacklight and red laser had no effect, but the filtered xenon flash still disrupted the circuit.
So it seems that UV, violet light, and low-intensity IR are not the culprit, but 532nm green light is one of possibly multiple wavelengths causing the issue. High intensity IR could still be one as well.