To the concrete points made in Rwanda's rebuttal, which can be read here:
The report was leaked to distract from allegations that UN peacekeepers did nothing to prevent an incident of mass rape in Walikale.
This is unlikely. The report was written by a team under the authority of the UN High Commission for Human Rights, not by MONUSCO. While MONUSCO did have a copy, all indications from within the UN suggest that it was leaked because some UN officials wanted to change the language in the report, in particular allegations that Rwandan troops may have committed acts of genocide in 1996/7. As reported here, Rwanda has threatened to withdraw its peacekeepers from UN missions if the report is published.
It is immoral for the UN, a body that failed to act during the 1994 genocide and then managed the refugee camps that hosted refugees and genocidaires alike in the Congo, to accuse the Rwandan army of genocide.