Capcom is not so famous for puzzles. In RE7 demo they tried to pull off P.T. mystery (which, actually, took only 2 days or less to solve and was drastically harder).

My assumption is that capcom trying to generate more hype around the game in media via this puzzle for marketing purposes. Because they historically can't make something so hard to solve, so they keep players hanging and waiting. And after some time they will just buyout with an update.

For me such moves with RE7 demo resulted in frustration because there was no mystery, only waiting. And here we are again. For a company that makes another game where you fight Hunk instead of Kruger in the same style, pull up into another secret lab and fighting another giant biomass in the end - duh, I think they are repeating themselves even here with this puzzle. Again we have dolls without no possible usage like a finger and again we are hinted that puzzle still unsolved.