I can recreate the WEBI report from scratch and it works just fine.
I went into the problematic report and re-pointed the BEx. Once that was done, I lost some random WEBI variables but the report works, however, it will take a lot of work to build it because of the lost WEBI variables and charts/graphs.
There have been no BEx changes made.
I can run the report just fine through the standalone WEBI rich client. I only have problems through BI Launchpad.