I think Baja and the others make some very good points about watering Aloes in pots.
To me, it is not clear from your pictures, which leaves are being affected by the shriveling and yellowing. New leaves just opened up from the center of the rosette or older leaves that are among the outer layer of leaves of the rosette? If the latter this could just a normal part of the lifecycle of the plant (following Baja's comments): older leaves sometimes die off as they are being replaced with new leaves as the plant grows and in addition many Aloes suffer significant leaf die-off during their dormant period and it might suggest you have been watering it too infrequently. Turns out that xeric plants that might be OK without water for weeks to months at a time when in the ground, become almost as water needy as many regular houseplants when put in pots in a low humidity environment. I water my in-house Aloes at least once every two weeks when the heat is one and if necessary more frequently.
However, if it is the new leaves that are showing this behavior then you probably have a problem that goes a little beyond a simple lack of water.
From your last picture, it would seem that these plants have very few roots. If those were the roots left after you took the plant(s) out of their pot/soil, you probably had significant root die back at some point. Given how full of plant that pot was there should have been a pretty tightly held together rootball in there. I suspect the leaf tips are drying out because the plant has lost a lot of root mass at some point. This can happen due to under and over watering, but overwatering usually leads to rot that more often than not also gets the plant itself. So this might also point to this plant not quite getting enough water.
I think the advice of very fast draining soil is really good (I use 50% pumice with 50% cactus mix), but if you go to that you need to up your watering frequency, because that kind of fast drying soil will be dry in a matter of days, not weeks, especially in-house when the heat is on, and just watering once a month will drive the plant into dormancy leading to loss of root mass, followed by drying out and yellowing of leaves.
