First page header text formatting not cascading to some parts

My goal is to add a piece of text to the first page header with the user-1 style. Ideally, I'd add it as text to the first page score header, and the same text with the user-1 style would appear on each part (tenor sax, baritone sax).

FYI - this file was updated from ver 3.

Steps:
1. Add the text "#01" to the first page header of the score and apply style user-1. I did this via selecting the header frame and right clicked, selected Add > Text
2. Open tenor sax part. "#01" in 40pt with a rectangle aligned on the right appears in the first page header as expected.
3. Open baritone part. "#01" appears in the first page header, but not in the correct style. It is in a smaller font without the rectangle on the left side. I cannot select the text on the baritone part.

If I open the baritone part first and the tenor second, the behavior is the same. I can't select and format "#01" on the baritone part.

Looks like my only workaround is to add the text to each part separately. the result is that the score and the parts have both pieces of text: one displaying as desired, and again on the left in the smaller font without a rectangle.