AmandaLouise, I think you may have misread or misinterpreted what I wrote, so I'll explain it a little more for you. I wrote: "I found out they had been quite active during those years, but I was completely amnesiac about it". That means that the dissociative walls were back up - the alters that had previously been fully coconscious with each other and the host lost all coconsciousness and returned to fully amnesiac and independent 'lives'. Why that happened is something I will not go into here.
I can assure you, however, that 'cracks and holes' in cement walls are far from permanent, and can easily be reconstructed by the very same ones who built them in the first place.