Don't confuse "when a match is contributed" with "when a match is calculated."
You can have a match that is calculated on a payroll basis, but they are deposited after year end. It doesn't happen often, but I have seen it. (Likewise, I seen annual matches deposited each week with the deferrals.)
The only match that must be deposited during the plan year is when you have a Safe Harbor Match that is calculated on a payroll basis. Then, the match must be put into the no later than the end of the quarter following the deferrals.
Having a true-up on a match that is calculated on a payroll basis is silly.