How to correct failed match coverage test?

Plan utilizes Fail Safe provision for coverage (so no ABT, here).

Plan (just) fails coverage for the match by three people.

The plan document says who the plan needs to cover, but it does not say what benefit these people must get.  Unlike a non-elective contribution failure, a match benefit would seem to be based on deferrals.  Often, the people not benefitting don't ahve any deferrals.  

So, does the ER give them some sort of QMAC?  To what level?  The groups ACP?  (ACP including voluntary after tax?  yes, it's still a thing!)

I'm sure I've seen the answer somewhere before, but it's been many years since I've had a plan fail the match portion of the plan.

I always thought of the solution as you do make them "match eligible" - but if the formula means they get zero, then that's still the case.  The real impact now is your denominator for your ACP test has gone up by 3.......which may or may not have a material impact on your results.

Come to think of it, if your plan has voluntary after-tax, then wasn't everyone covered under 401(m)?  So that even if some people didn't get a match, that wasn't the only way they benefited....