Firstly, u can use any Kiwi Kleen except dark blue OXY FORCE, cos OXY means got bleach. iRobot specifically say no bleach & no wax for Scooba.
So u can use fragrance Green Tea, Lavender, Apple, Morning Spring, Super Active (what I'm using).
Secondly, if u spilled some sweet liquid, using Scooba to clean up that spot WILL work, but I still think Paper Towel will be faster. Considering the sweet stuff will be sucked up by Scooba, a little will be left & scrubbed by Scooba brush, then squeegy up. So u end up with sweet tank, brush & squeegy to rinse clean, ur rear foam tires & front rubber wheel might get the sweet liquid too. But... if u're cleaning whole room anyway, then the rinsing will be worthwhile, and the multiple passes with clean detergent will also gradually "unsweeten" the brush & squeegy.
Lastly, I use Scooba on bathroom tiles, but my soap scum stains are inside the shower area which is shielded by sliding door.
If ur soap stains are all over bathroom, I do not see an issue using Scooba, but do rinse Scooba tank properly to prevent any soap sediments.