I have been doing ADP/ACP testing since 1983, yes 1983. I have never heard of such B.S. on ADP failures. No matter how the match was determined (and deferral), it must be tested on annual pay. When you match per pay and no true up, it is almost always under the ideal match.
So they have two problems - one is testing definition of compensation, and the second is identifying the regulation that supports using only pay while deferring and not pay while eligible to defer. Note that exceeding a 415 or 402(g) limit does not disqualify pay, only exceeding the 401(a)(17 limit.