Hello Jessica
Philip mentioned above that he tried SP06 and everything worked fine. You've added a refinement in that you describe having stacked hierarchies in the rows, which you merge together using the "Compact Display In Rows" option.
I haven't tried SP6 but I did try SP9 which was recently released and can confirm there is no issue. This is demonstrated in the following screenshots...
Stacked hierarchies before they are compacted. Note that I have deliberately set the Sales Person info to be displayed as "Text : Key" but the Country is displayed as "Key : Text".
After we compact the rows and expand "Nancy Davollo" we get...
Finally we then export to Excel. Notice that the different display formats remain intact...
I hope this addresses your concern.
Regards