I neglected to address the "allocation" comment, and this part by @rbynaker : "The "catch up" rules require that the spouse make their own $1K contribution to their own account."

There is only 1 "catchup" amount. From the article I linked, which I chose because I spent time reading a few of them to be helpful to @treasur2 and liked how the one I linked worded the scenario. I found it easy to understand, even though their Values are from 2016. This part, specifically:

"The IRS gives married couples three options: Split the family contribution evenly between the spouses, allocate it according to a division they both agree on, or put 100 percent in one spouse’s account. In any case, the IRS treats married couples as a single tax unit, which means they must share one family HSA contribution limit"

So, yes, there is an Over-contribution condition for these taxpayers. Hence, Penalty applies.