Layers published with NAD_1927_To_NAD_1983_7 (wkid 8555) transformation do not transform correctly in Portal

gis_mags

I have been experiencing an issue where any composite transformations that include the NAD_1927_To_NAD_1983_7 (wkid 8555) transformation do not transform properly when published to Portal. 

In the example below, I published the same layer three times:

1. once with no transformation at all (white circle)
2. once using the wkid 8555 transformation set in the Map Properties (red circle)
3. once after having run the layer through the Project tool using the wkid 8555 transformation (red triangle).

The circle and triangle should been top of one another; however, in Portal they are offset:

I do not have this issue when using other transformation paths. For example, here is the same process using NAD_1927_To_NAD_1983_NADCON (wkid 108001, latestWkid 1241):

 

Any ideas why this is occurring? The layer's JSON does indicate that the data is being published with the transformations I think they are:

gis_mags

Update, I believe this issue occurs due to having supplemental ArcGIS Coordinate Systems Data installed (Install supplementary coordinate system files—ArcGIS Pro | Documentation). The supplemental data includes NADCON5 data, of which I believe NAD_1927_To_NAD_1983_7 (wkid 8555) is a part.

Can anyone verify that transformations which rely on the supplemental coordinate systems files will not publish & display correctly in Portal? Am I on the right track here?

Related, I am not sure how to determine which transformations rely on supplemental data without individually testing each one, or by uninstalling the supplemental files...