To explain a bit further as to what I saw when working on a case (not sure if it was yours or someone else Justin1911).
vCD Inventories all Datastores individually as data type BIG INT, and then sum all Datastores in a given policy to find the total capacity (Also BIG INT).
BIG INT in SQL is a signed value between -2^63 (-9,223,372,036,854,775,808) & 2^63-1 (9,223,372,036,854,775,807) from MS SQL and there is no larger INT type at this time (that I know of). the "truncation" is when the sum of datastores size in bytes exceeds the maximum value allowed as a Big Int.
9 EB is an absolutely huge amount of data. The only time I have seen this data truncation issue happen, is when the Storage Device is incorrectly representing the capacity of a Datastore/Volume to ESXi/vCenter.
In a sense, we are seeing the problem in vCloud Director, but I can't think of any single storage device that can offer this. I have seen storage profiles in PetaBytes ... but that's a full order of magnitude away from ExaBytes.
So the solution, as mentioned, would be to remove the Datastore from vCenter Inventory and try to find out how or why the Storage Device is representing 9 EB when it probably shouldn't be.