I just reviewed the first demo with r_drawothermodels
10,000 - 10,900 tick : seems like wall hacks

23,000 - 25,000 tick : also seems like wall hacks

31,000 - 33,400 tick : can be explained by camping

36,000 - 36,500 tick : seems like wall hacks because He looked exactly at the person through the box and if it weren't for him tilting his screen twards him I would say that could be explained by checking common camping spots, but he looked at him.