VSE - text effect strip with alpha over blocks one clip...but not all

My application stacks several assets with all but the lower level clip set to alpha over. When I apply a text effect strip (with alpha over) the transparent text appears as expected, however it blocks one, and only one, clip.

In the images supplied:

(1) The top image shows a flag animation+two tinting layers+a year animation…with the effect strip text on top and muted. With the text muted, the date animation displays. Note that the “2003” is shown, but the text is not.

(2) The second image shows the same image stackup, except the text strip is unmuted…thereby causing the date animation to not be shown. My application keyframes the opacity of the effect strip text, which works fine with all assets except the date animation, which continues to be hidden when the effects strip is unmuted. Note that the “2003” is missing, but the text is shown.

The alpha over for the effect strip seems to apply to all layers except the date animation. I can assure you that all layers are set to alpha over.

All ideas appreciated. Thanks for your time.