I wonder if his departure has anything to do with the delay of the other courses? Maybe he took some students/staff/resources with him that were key to the infrastructure?
Although I am not aware who was behind the development and operation of Aiqus.
Not sure if you're referring to the current bunch of courses or the first three (AI/ML/DB). I'm assuming it's the latter. Aiqus was only used for the AI class. IIRC it was set up independently but someone before the course began and ended up being the pseudo-official Q&A forum (linked to from the main site).