Epic Report on a kanban board is a bit pointless - you can't associate issues to epics because there is no Plan Mode. There is also no estimation statistic configurable on Kanban boards, which cuts out half the information on the chart.

Either we choose to show it and make sure it works with the limited information available, or we do not show it.

EDIT: also observe in the attached screenshot that the date range picker appears on this report even though it has no use.