Relations with the IMG have always been neutral for as long as I've been in the SCRA (over 3 years now).
SCRA see the IMG as semi-kindred spirits. The did not so much revolt as simply leave and reform their own small government. A bloodless popular coup if you will. They don't work for any of the corrupted Houses, but instead are their own individual group making a new life for themselves.
There has been many times that SCRA has come to the aid of IMG in different areas of Sirius. While not overly friendly in relations, as I'm sure IMG has a few problems with how we (SCRA) takes care of some of our business, we are fairly cordial to each other. Added to that the IMG work sometimes with the RHA in O7, a known ally of the SCRA.
Plus, they're pretty much civilians. SCRA doesn't attack civilians unless they're drug-runners or slavers.