And therefore no need for an exotic mechanism such as you suggest. Consider the effects on the earthś atmosphere and surface of such an extreme event, even if mediated somewhat by our magnetic field.

As for Mars:-

The near-polar regions experience intense thermal cycling between winter (-125 C ) and summer (-20 C? ) This ~100 degree cycle is sufficient to cause cracking of the ground, differential movement of large stones vs. small particles, and development (over millennia) of polygonal texturesm on a characteristic length scale of a few metres (the skin depth of annual temperature fluctuations).

Despite what you may read, there is no EVIDENCE of thaw. Indeed, the evidence is very much against the development of even occasional liquid water - the mineral balance is wrong.

However, letś sit back and wait for some results. There will be surprises and puzzles enough for all of us, and we will all have to adjust our mental models of Mars to more closely match the observed reality.