It is still intentional clipping. It is not even accidental clipping that you are choosing to live with because some other agreement can not be made. It is intentional, PLUS you are not maximizing models into combat. There have much warhammer gold in our stock, make order when you need.
There is no stipulation that we can find that allows you to ignore those models for maximization just because they happen to be engaged with the Cygor in Warhammer. You are still required to bring the maximum number of models from both sides into combat.
Therefore, even if you choose to ignore the Appendix, Diagram and Manoeuvring during a Charge still applies. We are not buying the argument that they can be ignored because they are already involved in another combat. That is BS and not stated anywhere in the rules. Our professional warhammer Online gold service is online now.
If you are not bringing the max of models into combat, then you are not. It does not say unengaged models, just maximum number of models. Reworded slightly when applied to Multiple Targets (We know that is not the situation here, but the rule is reiterated here), the intent may be a bit more clear Note that after charging the unit must still try to engage as many models as possible from the intended target.
Clipping is against the Spirit of the Warhammer. How people can read the Appendix and still choose to clip, but even if you do, the charging rules prevent most intentional clipping, as in this case.