Would you still say that Soul Reap is the best blessing for Inithwe, despite the part about not making the kill non-revive?
Yes. The blessing only activates, if the enemy survives the initial hit and has a certain percentage of hp left. In this situation, you have no block revive with Soul Reap, but the enemy is at least dead - or no block revive without Soul Reap, because the enemy is still alive.
If Inithwe kills the enemy directly, block revive should activate as normal.