You missed it in the Datasheet... like they say, if you want to hide something, do it in plain sight!

Look at the CMCON Register bit 6 - COUT (stands for Comparator OUTput). This is the bit you read to get the Comparator Output in software. Example...

If CMCON.6=0 then goto BatteryFlat

The state of this bit additionally depends on your setting of bit 4 - CINV (stands for Comparator INVert).