Can I activate an open workbook without knowing name?

I have a macro that unprotects a workbook, copys and moves a worksheet,
activates the main workbook to re-protect it but I want to leave the user in
the new workbook. I dont know if the name is Book2 or Book3, etc

Sheets("Grid (2)").Move
ThisWorkbook.Activate
Sheets("Cover").Select
Range("C11").Select
ActiveWorkbook.Protect (["password"])
Now I want to activate the single sheet workbook that I moved (Book2 or Book3)