Unfortunately, no. In Standalone mode the IAP runs as its' own "private group" and manages / monitors itself only. As such, you would wind up with a total of 5 IAPs running in Standalone mode and you would have to configure each one independently and manage them via their own VC IP. To do as you are requesting separation via Vlans is the only option using IAP.
You could add a controller into the mix, which would take ownership of all 5 APs then this is possible. The controller would be the single point of configuration and monitoring and you could split the APs into two separate groups -- each group can run separate configs, hence separate SSIDs.