Text frame auto fitting with an inline image embedded
Hi folks,
I'm building a catalog in which each product's details are contained within an inline text frame. Within that text frame are various components - another text frame, maybe some text, a table. etc. I'll call the main text frame "frame a" and the embedded text frame "frame B". An Object Style is applied to Frame a, with the auto-sizing "height only" option selected. Likewise, frame b has the same auto-sizing options selected.
Frame b contains some text and it may also contain an inline image. If there is an image in frame b, the frame a auto-sizing on frame a doesn't work correctly - it allows frame b to extend out beyond the bottom of frame a. See this screenshot:

Frame a is selected.
Frame b is the one that contains the inline image.
Here's a link to the InDesign (CC2019) doc in case anybody would like to have a look at it:
https://www.dropbox.com/s/rkjn1qfg0gtp1xf/CatalogUS.indd.zip?dl=0
Thanks for any advice you can offer!
Pat Bensky