A) An argument to powershell.exe which Office will not supply when executing the ps1 file or
B) Interacting with the powershell window after it's opened (which you can't do without already having some sort of code execution) or
C) The execution policy being set to something that allows unsigned code.
A and B are impossible, and C can be locked down with group policy to the point that local administrator rights can't bypass.
Executing a ps1 with the appropriate parameters after executing something else may be possible, but also redundant.
A) An argument to powershell.exe which Office will not supply when executing the ps1 file or
B) Interacting with the powershell window after it's opened (which you can't do without already having some sort of code execution) or
C) The execution policy being set to something that allows unsigned code.
A and B are impossible, and C can be locked down with group policy to the point that local administrator rights can't bypass.
Executing a ps1 with the appropriate parameters after executing something else may be possible, but also redundant.