Yes, I confirm as well: the Marquis can't be bypassed (although there are pretty big places between him and the castle

), so You are right: 14 is the minimum.
Call Colossus works (I mean you can change the result with several methods), but neatness always gives the same result. (But now I understand your idea, regarding this).
Impossible no loss with peasants only. It seems extreme hard. (Till sy do it!

)
I think the invisibility, and death star and so on tricks could be work, but will You have enough recources to build up the hero before the very first battle??
BK. I have had splinter of darkness only once, and just in that game I haven't used BKs at all. BK is very very strong without any leadership modification.
And yes, You need teleport lvl1, and if You want to get sure chance, You need to be a Mage to put eviln and make teleportation in the same turn.
Lvl 3 eviln gives back 30% of the original HP of the stack, which means with four eviln you would get back more than the whole HP. I don't remember any in my games using eviln more than 4-5 in a battle. As I remember even Baal was killing only about 10-12 BKs in a turn (with lvl3 stoneskin), so with a +100 BK stack seems doable. I like droids very much (very good in noloss games, quick and tough), and I like BK as well (bit slow), but my opinion (without trying what You did

): BK is easier way, than droids.
Perhaps some weeks later You will settle this issue?