Clogged EGR can and will NOT cause engine failure! It is ONLY an emissions device/system to reburn SOME of the spent exhaust fumes and assist with cold starts. It WILL set a check engine light.

Clogged PCV valve will also NOT cause engine failure EXCEPT that after it blows the seals (rear main usually), the resulting low/lack of oil WILL cause engine failure very quickly. Clogged PVC does not usually set a code either...