Not to mention that, Tsukune losing control during his fight with Akua, would definitely cause Alucard to fully awaken, and I have to say that a situation where the rest of the protagonists would need to deal with a rampaging Tsukune and a fully awakened Alucard would be a little too much to deal with.
After all, we had seen how difficult to control Tsukune is, in his new berserk state, and if we combine that with what Alucard demonstrated in the flashback to Moka's childhood - well, in such a situation, I can't think of anything else, but a bad ending, where the player needs to restart from the last checkpoint
.
Since, Tsukune and Ruby have been teleported to some alternate universe, that is most likely separated from Fairy Tale's HQ, Tsukune can probably rampage there all he wants and it won't influence Alucard's current state...
The downside is, that Kuyou will probably try to seriously kill Tsukune, even in his rampage state, so the situation definitely won't be ideal, but I think that's the reason why Ruby has been teleported along with Tsukune to try to remedy the situation a little, and keep Kuyou busy, until Tsukune regains control over his powers.
So the situation can't be called "ideal" but honestly, we all need a little drama to spice things up.
