carbon dating doesn't work and dust getting compacted into rocks only takes weeks to start and seals everything inside it up, usually meaning the bones are permanently preserved
this is what happens when the earth suddenly rotates 90 degrees, all the oceans go the opposite direction for a while and then run back down to the low areas again... in the process they wash away all the dirt and dust that built up in normal times from the weathering of rock
"sedimentary rock" is literally mud that has piled thick enough to squash all the water out of it