Try this...
Open windows explorer and navigate your way here...
C: \ Program Files (x86) \ Topgolf \ WGTLauncher
...open the WGTLauncher folder and rename the folder golf. Rename it golf1 or something like that, then run the game again to see if the update installs correctly.
If the update installs correctly, then you can delete the folder that you renamed golf1.
If the update still fails, go into the golf folder and double click the golf.exe file, this should run the game without trying to update.
Try launching the game as you would normally, every so often, just to see if the update will succeed.