"...dating methods can be wildly wrong."


No... if you understand the physics behind radioactive decay, it cannot be "wildly" wrong. It is not accurate to days or weeks, but in thousands of years it is pretty clear. It is not about "how much carbon", but rather the amount of radioactive decay in any amount of C14.

" rock formed from volcanic action this century have been "dated"as millenia old.

*sigh* volcanic deposits are FROM material that was melted or disturbed from MANY ages. It is perfectly possible for magma from last week to have components dating much longer ago.