Darryl’s Analysis

Environment
This window situation is great for the Monstera.

Effort
I think this is much too small of a pot for this size plant.  As a rough guideline for Monstera deliciosa, I try to use a pot that is about the same size as the largest leaf diameter, up to 16″.  Your plant is definitely putting up leaves larger than that so your current pot (looks like 12″) is definitely too small.

When soil is evenly moistened and healthy roots are taking up the moisture, leaves should take 2 or 3 weeks to fully open.  Leaves staying closed for longer than this occurs when there is inadequate moisture in the soil.

I suggest you repot the plant into new soil (be sure to gently loosen the roots and some of the old soil off) and use a 16″ wide pot.

Bottom watering doesn’t work well with very large volumes of soil – pour water evenly and thoroughly moisten all parts of the soil.  I personally never bottom water as I find it time-consuming and tends to leave dry pockets if soil is compacted.

Expectations
Even if you repot the plant, this leaf may never fully open as it appears to already be damaged from the dryness stress.  Hopefully the next leaf will emerge problem-free.

Monstera deliciosa are excellent long-term houseplants but most plant care tips and tricks are vague and unhelpful.

Cut through the noise – learn from my course.