Not sure if this issue is still persisting for anyone but I did find a way for QB desktop enterprise to let me install the most recent payroll update.
File > Log out
File > Open / Restore Backup
Select a backup to restore that was made after the release date of the most recent QB payroll update but before you noticed the update will not download. (Mine was about a week old)
When you restore it will ask you to name your company file, be sure to CHANGE the file name to include the backup date so you do not write over your current company file. You are only restoring to perform the update!
Once the restoration has been performed:
Employees > Get Payroll Updates
Don't forget to be patient during this process it takes FOREVER!!!
Once the update has installed close the backup file and reopen your original file.
Go to Employees > Get Payroll updates to ensure the tax table number is still updated to the most recent version.
