I agree, the points that I made are highly speculative but still things within the series seem to be inclining towards the possibility that Sari is a cyborg of some sort.

When it comes to lack of mother on other characters such as Spike and Shutta, well the plot, setting and circumstances were radically diffferent and although Shutta's father comes close, he isn't portrayed as a socially isolated robotics super genius. I could be wrong, but didn't Gou mention his mother early in the series?

It is well within reason that the Skunk professor would indeed 'build' a kid.