I am in the exact same dispute with AC. The first leg was on LH, who failed to put the bag on the plane and AC lied to me for three days that they knew where it was but wouldn't tell me. Then it turned up on the porch. I had packed business wardrobe that I needed during on that third day, and they have refused to compensate for what I had to buy as a result. They did not cite a policy about home airport. Instead, they claimed there were "too many variables" and they try but don't promise that bags will arrive with the passenger. What? I've rejected their rejection on the basis that there were no variables at all. The bag did not get lost at the connecting airport on my flight. It was routed three days after I flew via a different connection. I checked in 3 hours early. The originating airport was small enough that there is no reason the bag couldn't have been loaded other than "oops I forgot". And to make matters worse, AC agents were evasive and dishonest in the process of trying to get information from them about whether I could expect my business wardrobe before my next trip. I didn't want to go shopping but I had no choice by the third day. I don't know why AC doesn't get in my corner and support their loyal customer, and recover the compensation from LH. So far I am still in the slow-moving complaint mechanism, but I've got nothing but time to keep complaining.