Hmmmm. Technically, the OP's camera is more than capable of taking the kind of picture in question. Except for one thing, additional light. This scenario is no different than any grip-and-grin shot. I would think seriously of an off-camera flash where you can dial back on the exposure. I hate to say it but you need to add some more light you can control.
Back in the day when they had this thing call "film", this was a slam dunk. And they didn't have any ISO 50 gazillion to do it with. Manual mode, ISO 200 or 400, 1/30 sec, f5.6 (or 8), second curtain sync, dial back the flash 2/3 stop and let the system decide how much flash to add. I have to admit not being familiar with Olympus flash algorithms but this is pretty standard with Nikon and Canon; can't see how Oly would be that diff. The slower speed and second sync will allow ambient light in so the flash and camera exposure system should cut off the flash when there is enough light to get an accurate exposure.
If you want natural light shots with no flash, the only thing I know of is to buy the most current generation digital with high ISO capability.