If I were a YEC, I might be comfortable appealing to a miracle to solve the mud problem. “God wanted the mud to dry up faster so that normal life could resume, so he made it happen.”
The idea of accelerated radioactive decay is much tougher theologically. “God miraculously sped up decay because… he wanted lots of radiation and heat… except that would kill everything and melt the world… so he miraculously got rid of it… leaving only the illusion of age.”
Previously discussed in The Burning Bush Reversed: the Unbiblical Miracles of Young Earth Creationism