I think it's possible that Dai did request a donation, but not as part of a quid pro quo.
If he went into the meeting thinking it was about campaign fundraising, while the lobbyist and her clients were there to talk about something coming before the council, then there was probably talking past eachother, confusion, arguing, etc. "I need resources to spread my message" seems like the kind of thing you'd say to try and clarify the purpose of the meeting, what he wanted out of it, ect. It feels like there could be some lying by omission going on, because there's a lot we don't know about how the meeting played out.
Given the way he's angrily talked about the meeting as a bait-and-switch (and the lobbyist's statements, and that it was arranged through campaign staff), that's how I picture it went down. Firing his campaign manager, by comparison, was a rather clear choice, because even if she didn't phrase it exactly as she meant to, offering to potentially "rethink" their position in exchange for a donation is a clear solicitation of a bribe.
I find the timing of the story to be suspicious. Some unknown third party leaked this story right after Dai won big in Ward 6, but before the conventions the next day. The fox article was posted online at 7:21pm, well after the convention was over. The delegate totals were announced a bit before i posted them here at 12:27PM, so by 12:30 I would assume Carter's, Harris', and Thao's respective campaigns had all received word of the results from their people on site. It was apparently fox's lead TV story that night. Dai's campaign pulled their staff from Ward 3 the next day to shore up their firewall in Ward 7 because of the news that broke, but they were going to contest it hard before the abrupt change.
The largest sticking point for me might be that Sarah, who is apparently experienced in these matters, would arrange the meeting through Dai's campaign staff.
At ward 6 when my Grandmother and I were talking to Dai about sidewalks and disability mobility issues, at one point in the conversation he outright said "OK, here is the point where I take off my campaign hat and put on my City Council hat", and offered us some immediate help and information as it pertains to his job as a city councilman (changing gears from talking about potential policy changes before his statement).
The way in which he deliberately delineated between his two roles (including stuff like body language that I can't convey through text) sticks out in my mind, and makes my gut say it's something they have been conscientious about, and that they probably try to stay clear of situations like this. The emphasis on this separation has also been mentioned repeatedly recently by various experts and in various articles on this topic.
The difference between the care taken by Dai to keep the two roles separate, vs Sarah's lack of care, seems odd, if Dai is the one who solicited a bribe.
Just my 2 cents.