W/o,
Like the others have said, do a bit more investigating. I would take a peek in the hole where the grill cover is to start. I am just wondering why the builder put the angle in to start with. Sometimes when there is a little extra space, the plumbers and electricians feel they have to mark their territory by running something through it.
If there is nothing inside, it shouldn't be a problem. That being said however, I would have someone with experience come by and look at it. Don't rely on us here totally and start ripping your house apart. Get a second, in-person opinion.
Mike Hawkins