Did you have a 90 at the end of the line on the pump truck. What size opening was at the end.
I just poured 70 cubic meters of ICF earlier (11 feet height total) this month. While I'm not a newbie, no way was I as splashed like you were nor did I have much separation.
PM me if you have any questions. Kudos for taking on such a project. It will be immensely satisfying and rewarding eventually