Dunno. Cactus do like direct water they just dont want the roots to sit in soggy dirt, watering from below might have left them dry and dead on top. Also some of those cactus look like they have sun damage, when a normally green cacti starts turning purple or pink it usually means they got more sun than they were adjusted too. However the tips on some look green and fresh so maybe it was just a short period of exposure?
I'd say give them a good water with some liquid fertilizer, if your worried about to much water in the roots you can switch to terra cotta planters, a cactus/palm soil, and or add lots of pearlite till it rapidly. I doubt it will fix the damaged sections but at least your cacti's new growth will look good.
