Hey all, I'm new to the forum, so catching up on some posts and this one interested me.
I've also had some transactions with HA, and looking at many of their poster auctions over the last few years, I have also found many examples of inaccurate descriptions (mostly Australian posters where later re-prints are offered as first release printings, or they are just not described as a re-release; and others where the condition is inaccurately described and damage is not noted or the condition grade is inflated). Their grading consistency is not great. And as you suggested, for the fees they are charging, they should be investing the time and resource to be as accurate as possible. After a purchase, I was even sent the wrong poster once which had to be returned, and waited a good 3 weeks to receive the correct lot.
In saying all of that though, they are a very large business now. Which I think is part of the problem. Quality control suffers as businesses grow and scale. It's not an excuse, but a problem they need to be vigilant about improving.
Although they can be slow to resolve a complaint, if you are persistent they will eventually. I've received a couple of refunds as compensation for errors and damage.