There are TWO big errors in your thinking. 1. Israel is not a signatory of the ICC so it cannot complain (but can be complained against, if the crime was committed on Palestinian land. 2. Why should Abbas worry if Hamas will be asked to answer questions?
Israeli teen lightly wounded from stone throwing in West Bank settlement of Kiryat Arba (Haaretz)
from the article: Israel freezes UNESCO funding after Palestinian membership