There appears to be a bug in the Toad Formatter when using the ListAgg() function within a Pivot. The formatter does not recognise that “Within Group” is valid and so fails with syntax check. This can be demonstrated with this simple query.
Select *
From ( Select 'Cheese' a, Level b
From Dual
Connect By Level <= 5)
Pivot
(Listagg (b) within group (order by 1) for a in ('Cheese'));