#1 : judging from the ruin and the moss and other weeds on the godess's temple, her power and influence had already faded away long before her capture.
Well a goddess can't be sitting around in a temple all the time.
So long as the sanctuary exists, she will, even without any rituals, manifest in the temple once every metonic cycle.
Just to see how things are going and maybe do some housekeeping.
If the proper rituals are held she will of course appear on all the appropriate feast days of sun and moon,
and tend to her people, reward the good and chide the evildoers ...
that is the point of those rituals.
There have been times in the past already, when upon manifesting, she found that her cult was in disarray ...
due to plagues, natural disasters, war and such mishaps.
But of course there's nothing more effective to restore a cult than a goddess appearing in person...
so until now, she always managed to set things right again.
But, after generations of planning, a group of deicidal nihilist heretics managed to capture all her priestesses...
and torture out of each of them, the one fragment of the secrets of the Goddess that she held ...
all put together, this gave the heretics enough knowledge to bind the Goddess ...
and proceed toward their goal, of sacrificing a living deity to the nameless void ...