List all Site Collection Admins Powershell

Malgorzata_SITS, I ended up doing what I suggested above.  That was the only workaround I could come up with.

Here's the last powershell script I ended up with (It was quick and dirty, so no warranties, use at your own risk, etc.)  You'll need to update "domain" to be your own.

$username = "$env:username@domain.com"
$Sites = Get-SPOSite -IncludePersonalSite $true -Limit all -Filter "Url -like 'domain-my.sharepoint.com/personal/'"
foreach ($Site in $sites) {
	$URL = $Site.URL
	$Admins = Get-SPOUser -Site $URL -Limit all | Where IsSiteAdmin -eq $True | Select-Object @{Label="Site";Expression={"$URL"}},@{Label="AdminName";Expression={$_.DisplayName}}, @{Label="AdminLogin";Expression={$_.LoginName}}, @{Label="RemoveNonOwnerAdmin";Expression={If ($URL.replace("https://domain-my.sharepoint.com/personal/","") -ne $_.LoginName.replace("@","_").replace(".","_")) {"Set-SPOUser -Site $URL -LoginName $($_.LoginName) -IsSiteCollectionAdmin `$False"} else {""}}}
	if ($Admins) {
		$Admins | export-csv c:\temp\OneDriveAdmins.csv -NoTypeInformation -append -encoding ASCII
		} else {
		Set-SPOUser -Site $URL -LoginName $username -IsSiteCollectionAdmin $true
		Get-SPOUser -Site $URL -Limit all | Where {$_.IsSiteAdmin -eq $True -and $_.LoginName -ne $username} | Select-Object @{Label="Site";Expression={"$URL"}},@{Label="AdminName";Expression={$_.DisplayName}}, @{Label="AdminLogin";Expression={$_.LoginName}}, @{Label="RemoveNonOwnerAdmin";Expression={If ($URL.replace("https://domain-my.sharepoint.com/personal/","") -ne $_.LoginName.replace("@","_").replace(".","_")) {"Set-SPOUser -Site $URL -LoginName $($_.LoginName) -IsSiteCollectionAdmin `$False"} else {""}}} | export-csv c:\temp\OneDriveAdmins.csv -NoTypeInformation -append -encoding ASCII
		Set-SPOUser -Site $URL -LoginName $username -IsSiteCollectionAdmin $false
		}
}