Where do you find the interpretation that the semiquaver should not be linked with the dotted half-note? I have not played this movement myself but I cannot recall that the bass rhythm should be taa-taa-ta-taaaaa, but rather taa-taa-taaaaaa (Silly expression, I know.)
I don't know what a crotchet is, but according to the note sheet, indeed you should play the A flat (I think you confuse many readers here by writing a moll, the right word is A flat here) despite that the "main beat" lies still. Of course this sounds impossible, but when you practice, you will probably omit the underlying accompaniment first and just play the A flats that are the heavy beat in this bar. The rest is, as my teacher like to say, "just decoration". It should be heard in the background, sort of. So first you play the third A flat in the bar, which is a semiquaver, quite firmly and with the pedal down. Then you keep holding the pedal down and play the note again but much lighter, as a part of that underlying accompaniment. So I see it is a combination of different dynamics and pedal work.
At least I THINK you can hold the pedal during this bar, but I have not tried yet. Someone who knows how to play this piece can take over now, please. I am only guessing here, but according to my teacher, on a similar case we discussed, you do like I described.