Quirk or Bug in Add Join / Export Features Pro 3.3?

[JillRKelly]

I've been working with the new Spatial Join that apparently no longer does "merge rule" summaries.

Wanting a join count and other summary statistics, I followed the process one would use in QGIS:

Spatial Join as one-to-many, then run Summary Statistics to count and otherwise summarize fields per case field entry.  Worked great.

Next step would be to re-join the Summary Statistics table back on to the original FC and then Data >Export Features that result. 

The Add Join works, but the Exported output weirdly and stubbornly omits the Frequency and other calculated summary fields.

Worse, there seems to be a way to add them, using the Fields drop-down in the Export Features tool, but Add is greyed-out.

I am a bit suspicious about that harder grey line between my join key field (ADMIN_NAME) and the frequency fields.  Why in the world would I not be allowed to export this feature class with its legit joined fields?

Project Package: https://yalemaps.maps.arcgis.com/home/item.html?id=21f7e990d9dd454a87cb7bff2320b2d0

video demo of the problem:

https://youtu.be/OtRNiMHJEpQ

[JillRKelly · Accepted solution]

Solved: It is a quirk. You have to use Add Fields in the Fields section of Export Features, click the checkbox next to each field you want to add, and then choose "First" from the little picture icons below. That makes the Add button live. Obvious, right?

PS: Copy Features does it right the first time with simplicity, so that is what my class will be learning.