Delvin Mallory Bug - "Where You Hang Your Enemy's Head" Quest

[Francis]

I'm getting very frustrated due to the fact that Delvin Mallory of the thieve's guild seems to have irreversibly bugged out.

As part of the quest written in the title, I must speak to him to progress in the quest and furnish the new sanctuary.
However, no dialogue box opens when I talk to him and he can only say two sentences over and over.

I read online that completing a seperate quest for the DB would reset him, though I tried this and nothing happened. He was still glitched.

I've tried attacking him (then paying the "fine" to the thieves guild for breaking their rules) and this makes him no different. Pickpocketing him unsuccessfully hasn't helped, either.

I've tried various console commands like setstage to progress the quest, resurrecting him, restarting the quest, etc. but that only seems to have deleted the quest entirely as the marker above his head disappeared and the quest is not in my journal.
Loading back to before I started the quest entirely didn't help and he was still unable to converse.

Could I please have some help with other console commands I could try? Or even a method without console commands, I'm completely stuck.

Thanks

[EleventhStar]

what are the two sentences he says over and over? do you have any quest from him outsanding, in particular the special city jobs?

[Trigger]

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