I found some weird behavior when trying to Create a View (Sheet) Selector for Your Dashboard with tree maps and word clouds that is similar to what you described. I think the issue was caused by not having anything on the Rows or Columns shelf. To workaround this, I created a calculated field to place on the Rows and Columns shelf of my word cloud views and then hid the header.
In the attached workbook this calculated field is named Header and is placed on the Rows and Columns shelf. After placing the Header field on Rows and Columns I right-clicked the field and deselected Show Header.
As long as I had the Header field on Rows and Columns and the worksheet size was set to Standard, the worksheets appeared and collapsed as expected when selecting values on the view selector parameter.
Let me know if this helps! If not, can you provide a packaged workbook illustrating the issue?
wordcloudsheetselector.twbx 1.3 MB
Thanks Sarah. it worked for me