Do the level layouts vary when "visiting previous levels"?
Every level has several layouts, and only certain layouts contain Artifacts. If at first you got a level layout that didn't have an Artifact, is it possible to get the right layout by visiting it on a second lap (aka "Visit previous levels" as the teleporter message names it).
Not having played with the new update, I cannot be 100% sure, but based on previous knowledge I would say yes, as layouts are randomly generated to a degree every visit.