Just pre-dilute it 1:1 and feed that to the SSK. Save up some rolls and run them all at once, if you are concerned with it going bad.
No, the SSK won't mix it with water on the fly, though you could pre-fill it with half the total volume needed, then have it pull straight XTOL from the bottle. With the mixing pill spinning it would likely mix it fine on the fly. You'd have to somehow pour the water in either between prewet and dev or skip the pre-wet. There's an access port to access the heating plate/reservoir for chemistry, you could probably pour in through there.
remember the continuous agitation will be somewhat different than typical tank usage too, so generally there may be some changes to development time needed as well, possibly.