I have been in such situation. Instead of exporting to Excel directly, could you Copy, open Excel and paste it? It worked for me. Although copying takes a bit depending on amount of data.
Go to Worksheet tab > Copy > Crosstab > Open Excel > Paste.
Hope this helps.
Just throwing this out there first - why not keep people in Tableau instead of going to excel ? Tableau also has the view full data function, and its faster to filter items in Tableau than it is in excel.
On the Data > data source > View data pane you can use the export all button to extract all data as a .csv - which you can open in excel
Alternatively, you can use the Worksheet > Export > Data or Crosstab to Excel menu option as well.