Mine was very similar to yours, it had that open area that looked like it was made for a second hole. I've attached a pic of the front / back for yah. I drilled a 7/8" hole and filled the gap with a plastic grommet found in the electrical section at Home Depot.
Back...
Can confirm, this works. I have a BR2001BL and I was able to drill a 7/8" line and plug it w/ a plastic grommit that was 1/2" thick. I can post pics / links if anyone is interested.