It is wrong in so many ways that it is hard to even know where to start. ERISA and the Code do not address whether it is un-American or not. On the IRS side, a plan, in order to be "qualified" must satisfy certain requirements in both form and operation. A plan that violates its provisions, such as required top heavy contributions, is subject to disqualification. I'll guarantee that your plan document does not provide for the return of contributions by Key Employees on the off chance that they discover too late that the plan is top heavy, or that they didn't understand or were unaware of the implications of top heavy status.
On the ERISA side, you have various anti-alienation provisions. When people are entitled to a benefit (as with non-key employees who are entitled to a top heavy benefit under the terms of the plan) you can't take that away from them.
There is no regulation that provides an override to the top heavy requirements such as you would like. So you are stuck with what the Code and Regulations say that you must do, which in this case, would be to contribute any required top heavy contribution.
I really recommend that you seek legal counsel first if you are planning to advise your client to treat this as "administrative error" - and review the terms of your E&O policy. You are really getting into some dangerous territory.
All this is just my opinion - others may not feel the same. Good luck.