Hello Brett and thank you for your quick reply and a warm welcome!
I have been playing with the USB host for a while and have not seen anything that would suggest to provide the interface’s class descriptor. The USB Host documentation is not really helpful, is it… anyway you made me went through this again and the auxiliary descriptors seem to be structurally similar to the class descriptors, so I will check whether the data are in.
Okay I have managed to get some device with a class descriptor and for those who are interested I confirm that the auxiliary descriptors do contain them as suspected.