I'd honestly recommend swapping to RADIUS, but if you have to use Meraki cloud...
Assuming a Windows computer, you can modify the rasphone.pbk file such that it won't try to use the VPN credential to authenticate to the server. It's fairly simple to do in PowerShell, so I've grabbed snippets from a larger client VPN install script of mine.
You will need to run this again every time you add a new VPN connection to the Windows client, if I understand correctly.
This only works if the rasphone.pbk file exists where it's expecting it to. So make sure you have a VPN connection setup and make sure rasphone.pbk exists.
Single user connection:
$pbkpath = $env:APPDATA 'Microsoft\Network\Connections\Pbk\rasphone.pbk'
(Get-Content -path $pbkpath -Raw) -Replace 'UseRasCredentials=1','UseRasCredentials=0' | Set-Content -path $pbkpath
All user connection - launch PowerShell as admin:
$pbkpath = Join-Path $env:PROGRAMDATA "Microsoft\Network\Connections\Pbk\rasphone.pbk"
(Get-Content -path $pbkpath -Raw) -Replace 'UseRasCredentials=1','UseRasCredentials=0' | Set-Content -path $pbkpath