Well I have seen the exact phenomenon at another resort. A chair that often built up a pile under the loading area, then a little dip/gully where they kept the area clear for loading and then a rise as the area received a lot of snow fall and the chair climbed a steep slope. I was thrown very hard to the ground 2 times that year on this particular chair and know exactly what the poster means by having you skis grabbed and then being quite violently thrown from the lift. I was not the only one tossed from the lift. It was a 2 person fixed grip chair that has a lot of swing after the lifty holds it back for loading compared to today's more stable high speed lifts. I was not the only person tossed from the chair that season or in past season as I was on the chair with a friend and had friends behind and in front who had skied the resort longer than myself and seen it in past. I know that I witnessed one other person, a lifty himself on a ski break, do the same thing a day or two after me.
I would be curious if it was a consistent problem with the lift set up over the season where you were. I was far more careful offloading after the first time it happened to me and that "Keep your tips up" sign I see at most resorts has a new meaning to me also,. And no, not everyone that year came off it and why me, I don't know. A lapse where I just didn't lift my tips enough I guess.
I hope you did take photos to help prove your case and you might consider small claims court if you have some evidence or can verify if it was an issue with the lift at the particular resort you were skiing.
BTW, I'm 5'5" on 173's and I don't think my height or length of ski contributed to my faceplant from the chair. I was glad I was only winded and had no injury or broken equipment but I can vouch for the fact that being pulled form a chair by your ski tips and into the hard landing area of a ski onload feels far more violent than falling while skiing.