A couple of thoughts, one of them a bit random. If the hooter and/or cruise control still work fine, it's likely not failure due to break in clock spring (aka roll connector) - the spring-like ribbon cable built into the steering column below the steering wheel (also manages the s/wheel airbag). But it still could be, there are around 8 wires, doing different jobs in the cable.
The random one - some Outbacks circa 2004/5/6 - airbag light can come on due to faulty solder joint in the circuit board built into the overhead map light cluster. If your car has overhead map lights - yes, I know its a Forester, not an OB - (near the inside rearview mirror), maybe, just maybe it could similarly be a dry solder joint there. I said it was random!