Forcibly transferring children (as Putin did) need not be present to determine that genocide has happened. Your link says: "In the present Convention, genocide means any of the following acts committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such:
1. Killing members of the group;
2. Causing serious bodily or mental harm to members of the group;
3. Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;
4. Imposing measures intended to prevent births within the group;
5. Forcibly transferring children of the group to another group."
The ICJ knows better than you what constitutes genocide, and have so far said that the case against Israel is plausibe.