Questions

Sure you guys timed it right, and didn't accidentally hit him right before he landed?

If not then chances are glitch?

I think we timed it right. Got training for Countering with spike. That means the timing was good, right?

And yeah, for our tests, at least with only a single spiker, we never got Normal or Hard Girgashiy to kneel.

In that case, where does the "rank A+" come from?

Testing in Easy mode.

rB didn't make the Easy-level girgashiy kneel, while rA did.

With a single spiker, at any rate.

If you can't get the Normal level to kneel, I'd recommend doubling back to Easy and verifying the requirements there.

Yeah, that'd be good to verify again, but... Hard to double back completely, without skill untrain capsules, though.

See about finding a rB spiker and see if that won't make Easy Girgashiy kneel.