Order of operations & parallel execution

I’ve got about ten db sql executors running ETL queries in tandem, as there are no dependencies between them. However, I have a loop node that will grant access across all the tables created, but I’m trying to find a logical means of forcing it as a last step.

Right now I’m guessing at the longest running node and using that flow variable output to force the grants to wait until that has completed. However, if I’m wrong or it happens to run short of another at any point in time then it will attempt to grant to tables that have yet to complete.

If there was some way to tie all the nodes to the grant node then it would have to wait for all, but most nodes only accept so many inputs so I’m wondering if I’m faced with having to create a node that operates as a traffic cop or if there is a node like that that already exists.