Hey, we just got an SB80 where I work, and I don't have alot of practical experience with it yet, but I have been using SB26s and 28s for shooting events with both N90S and F100s for years. Before that, we used 283s, 285s and FMs for this sort of workand shot all manual with bounce or slaved units as well. I don't see why you shouldn't be able to bounce a small strobe in the situation you describe, but the thing to remember is the TTL or the programmed TTL that the Nikons use (I don't know how you got the camera set up?). But the camera's "brains" aren't necessarily smarter than yours in certain conditions and they can be fooled just like auto flash by dark or light tones and big, expansive areas.....with the Nikons, usually you control the background exposure on the camera (like dragging a shutter on a manual camera) and control the foreground (the strobe exposure) with the controls on the flash. The speedlights meter off a pattern that's close to centerweighted too. Alot of times I shoot on centerweighted and skip matrix altogether....I really only use that outside for fill flash....
I use an SU-4 with the SB26s as well as the older wireless automatic slave function they had. The SU4 is a buggy PIA to use and needs constant monitoring if you're actually using it on the run--what we do is to have the fill light be on the camera in the form of a SB unit with a Stofen kicked up at a slight angle. We shoot in close with fast, wide angles, and put the second strobe on a pole with the SU4 attached with a SC17 cable. This way you get the sensor down close to you so you can aim it at the main strobe on the camera or wherever. The SU4 works by line of sight for the light from the main unit--when it kicks on, it fires the slaved strobe. When the main shuts off, it shuts off. It really works, but is a PIA when things aren't "right" for it. It also draws it's power from the strobes AAs. So, it acts weird when they drop in power. We run them all off Turbos, but they still need fresh AAs in the Speedlight to power the SU4 correctly. This way, the assistant runs around with the slaved uni (btw--we zoom that unit out to the widest setting--flood it out) and is, in effect either fill or main depending on where they are positioned and how the speedlight is powered up. We like to shoot cocktail parties & night time events like this, with the stofen unit acting as fill and the second light on a pole above the grouping--think people in black-tie grinning at the camera. Or we do shots with this second light as rim light or lighting the background....the SC17 cord is good for this because you can hide that second strobe and the remote SU4 triggers it.....when I play "human lightstand", I usually hold the SC17/SU4 in my hand and aim it at the camera....the most *important* thing to remember with multiple lights is that you need to shield the lens for flare or avoid aiming that second strobe at the lens....it really helps to have the second person understand lighting if you do it this as well.
FWIW, when I shoot events alone, I often put the second SB on a stand with a SU4 and turbo, and either use it as the main (direct) or the fill (bounce or stofen)....I shoot kids every year with history projects at an awards convention like this with N90s...I put the SB26 on camera with a Stofen and the second one on a stand off about 45 degrees right or left., a little higher than my head and titled down, zooomed out to 20-24mm. This is my main....I shoot on manual TTL, usually 60th at 5.6 or so with a 28 or 35mm lens.....the room that they held it in last year was about 13000 sq ft and painted black. Big, black pit with overhead work lights that were mercury vapor..it worked great, with both chrome and b&w film.