Block User Cannot Change Password

I'm attempting to rework this KB a little bit:

https://support.oneidentity.com/kb/320795/how-to-enforce-a-specific-value-for-user-must-change-password-at-next-logon-when-using-the-active-roles-web-interface

Original code

function onPreModify($Request)
 
{
    if ($Request.class -ne "user"){ return }
    if ($Request.Attributes.Attributes["edsaPassword"])
    {
        $Request.Put("edsvaUserMustChangePasswordAtNextLogon", $true) #Alternatively, use $false if desired
    }
}
Should I be able to change "edsvaUserMustChangePasswordAtNextLogon" to be "edsaUserCannotChangePassword" ?
Like so:
{
    if ($Request.class -ne "user"){ return }
    if ($Request.Attributes.Attributes["edsaPassword"])
    {
        $Request.Put("edsaUserCannotChangePassword", $false) 
    }
}
This tries using an access template to accomplish limiting access to the password options. But I'm only looking to block UserCannotChangePassword and leave UserMustChangePasswordAtNextLogon available. I tried applying it to only UserCannotChangePassword, but I could still set it to $true.
I also tried using a straight-up property generation and validation policy to force edsaUserCannotChangePassword to always be $false. That didn't stop me from setting it to $true either.
I removed the option from web interface but some of our craftier admins have learned how to use the quest cmdlets and realized they can set UserCannotChangePassword to $true to kind of exempt some accounts from our password policies. Ideally, I'd like an "Administrative Policy Error:  Setting edsaUserCannotChangePassword  to $True defies corporate policy"  Like you get when you set property validation on a normal attribute.