A one-level dip in CW samurai isn't actually all that bad. It probably wouldn't hurt you much, considering you're not getting any class features. It's certainly better than soulknife, considering that soulknife doesn't even give you a whole point of BAB.

Was there an alignment requirement in the build you just posted?

Alternatively, Fist of the Forest would be good to get Con to AC if you could swing it. Hexblade progresses BAB as well. Spellthief is always kinda nice (also way better than soulknife, because it gets you sneak attack).

I would swap CW samurai in for soulknife (that way you have 8 classes with 3/4 BAB progression still, and don't lose any fractions) and add in fist of the forest and hexblade.