The output only shows the invocation of looking for an instance of darktable running. No indication that the application it's self is running.
I am at a loss now as to how to see what all starts when darktable is started. I do not have it installed on my system so not able to look at the config files. As an alternative try this:
Start darktable and then run the "ps" command again, see if there is more than the two expected returns (??}
Begs the question "what is locking up what database" ??
ps au | grep darktable
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