Did you read the datasheet, telling you how to use the DAC output ?
The datasheet can be found in this link.
It tells you you need to use a 1K2 resistor and a 104 capacitor to use it.
That is the datasheet of the chip, not that of the module.
It is very well possible that some module already has these extra components on board.
I can’t tell off of your picture above, but i do know that the chip’s pin for DAC out, is the same as that for PWM+ out.
So it is always PWM+, and a resistor/capacitor combination will form the last and essential step of a close to real DAC.
So check for the presence of that resistor and capacitor, and if it is not, add them yourself.
100 µF ?
That's got to be way too large for this purpose.
So i googled to find a conversion table.
104 isn't 100 µF.
It is 0.1 µF, and that's more to my expectations for this purpose.
Try again with 0.1 µF and the original schematics.