Its not surprising. He is literally playing Omen on Icebox for first time. He doesn't usually play Omen and Omen hasn't been meta in Icebox before really.
actually its not his agent , i always see him doing worse on icebox compared to rest of the maps irrespective of what agent he plays. Jamppi is a great player but something needs to change for him on icebox
He´s the IGL, also he isn´t a natural IGL, he had to adoptave this role. It´s normal in a not natural IGL that that´s things happens, cuz many info that he need to manage.