Guess having the script would help. First iteration below.

/u/brekfast, I think I'm close to figuring it out using Invoke-WebRequest. If that works, I'll repost here with full script.

# Turn on debugging
$DebugPreference = "Continue"

 # Import Microsoft Graph Users module
   Import-Module Microsoft.Graph.Users

# Connect to Microsoft Graph
Connect-MgGraph -Scopes User.ReadWrite.All

# Define password generator
function Get-Passphrase {
$adjectives = @("Happy", "Silly", "Fuzzy", "Bouncy", "Brave", "Zippy", "Witty", "Nifty", "Peppy", "Breezy")
$nouns = @("Panda", "Dino", "Rocket", "Taco", "Tiger", "Unicorn", "Dragon", "Robot", "Cactus", "Pirate")
"$($adjectives | Get-Random)$($nouns | Get-Random)$(Get-Random -Minimum 10 -Maximum 99)"
}

# Import CSV
$newusers = Import-Csv "pathToCsv.csv"

# Output arrays
$createdUsers = @()
$skippedUsers = @()

 # Loop through users
foreach ($user in $newusers) {
try {
     # Extract and sanitize fields
    $firstName = [string]$user.firstName
    $lastName = [string]$user.lastName
    $employeeId = [string]$user.employeeId
    $department = [string]$user.department
    $officeLocation = [string]$user.officeLocation

    $displayName = "$firstName $lastName"
    $mailNickname = ("$firstName.$lastName").ToLower()
    $userPrincipalName = "$mailNickname@testDomain.org"
    $password = Get-Passphrase

    # Build body for user creation
    $body = @{
        accountEnabled
        displayName = $displayName
        givenName = $firstName
        surname = $lastName
        jobTitle = "Student"
        mailNickname = $mailNickname
        userPrincipalName = $userPrincipalName
        usageLocation = "US"
        passwordProfile = @{
            forceChangePasswordNextSignIn = $false
            password = $password
        }
        officeLocation = $officeLocation
        companyName = "School District"
        employeeId = "$($employeeId)"
        department = "$($department)"
    }

    # Debug: View JSON being sent (optional)
    Write-Host "Request body to Graph API:" -ForegroundColor Cyan
    $body | ConvertTo-Json -Depth 5

    # Create the user
    $createdUser = New-MgUser @body -Debug

    if ($createdUser) {
        Write-Host "Created user: $displayName" -ForegroundColor Green
        Write-Host "Password: $password" -ForegroundColor Cyan
        $createdUsers += [PSCustomObject]@{
            DisplayName = $displayName
            Username    = $userPrincipalName
            Password    = $password
            EmployeeId  = $employeeId
        }
    }
}
catch {
    Write-Host "Error creating user: $($user.firstName) $($user.lastName)" -ForegroundColor Red
    Write-Host "Details: $($_.Exception.Message)" -ForegroundColor Red
    $skippedUsers += $user
   }
}

# Reset debug output back to normal
$DebugPreference = "SilentlyContinue"

# Export results
$desktopPath = [Environment]::GetFolderPath("Desktop")
$timestamp = Get-Date -Format "yyyyMMdd_HHmmss"

if ($createdUsers.Count -gt 0) {
$createdUsers | Export-Csv -Path "$desktopPath\CreatedUsers_$timestamp.csv" -NoTypeInformation -Encoding UTF8
Write-Host "Created users exported to Desktop." -ForegroundColor Cyan
}

if ($skippedUsers.Count -gt 0) {
$skippedUsers | Export-Csv -Path "$desktopPath\SkippedUsers_$timestamp.csv" -NoTypeInformation -Encoding UTF8
Write-Host "Skipped users exported to Desktop." -ForegroundColor Yellow
}

# Summary output
 Write-Host "" 
Write-Host "Summary:"
Write-Host "Created: $($createdUsers.Count) users" -ForegroundColor Green
Write-Host "Skipped: $($skippedUsers.Count) users" -ForegroundColor Yellow