It is most decidedly not legal, but they had the largest condo law firm in the Chicago area on retainer who made the statement they wouldn't provide it. (Literally the lawyer I was recommended to use until it turned out... it was theirs.) Their lawyer's own website basically said the HOA can't hide stuff like this from owners.
Which is to say if I had had the time and money for a protracted court drama, I do think a judge would have literally laughed them out of the courthouse, but everyone involved knew the case wouldn't get that far.
One really fun fact I learned from this is lawyers mostly just email each other polite requests with the vague threat of "this could escalate to court" as the grease that moves things. And if one side doesn't think it'll end up in court they just... say no!