You can use below trick to achieve your requirement,
1] create a summary on uniqueattachedID across the group. This summary will give you sum of uniqueattachedID column. Suppress this summary.
2] Now go to the Section Expert of the group. Write formula for Suppress.
3] In formula you will write
if summary column (select this from reports field) > 0 then true
else false
I hope this helps!