Starting in the most recent MMOMinion update, it's always skipping dialogue even when the option is unselected as below. Cutscenes are not being skipped, it's only the dialogue skipping option.
I keep having to unload the bot on cutscenes I actually want to watch when going back and forth, it's rather annoying.
Quest mode was originally made to run afk, so it was never a priority to support watching cutscenes and dialogue, plus in the beginning they would cause issues if not skipped.
If you switch to assist mode before the cut scene you with to play, it will not skip either. Otherwise, you need to wait and see if the devs care enough to make this configurable and if it doesnt cause issues. Yes, the toggles were added to quest mode, but they seem to conflict with the settings under "Hacks" which automatically reenable when quest mode is selected.
On fresh boot of the game, if nothing has been started, dialogue plays and is not skipped.
Then, as soon as doing anything with the bot (gardening plugin, quest mode, anything) causes dialogue to be skipped until the game is restarted, regardless of the
settings in Advanced Settings. Settings in Quest mode ("Enable cutscene / dialogue viewing") are ignored, I can set them to either value and dialogue will be skipped.
Finally, if I run assist mode, that does not fix, dialogue continues to be skipped.
Looks like it was fixed. Now if I switch into assist mode after running quest mode and start+stop assist mode once, dialogue plays again. So I'll use this as a workaround.
Of course quest mode still skips dialogue even when the settings are set to "Allow reading dialogue" but, as rsilva mentioned, this is a low pri feature.