First on the basis that the reference form is currently open then the WHERE clause need changing from this
... Where [ScopeProjectPPMCNumber] = [Forms]![NewScope]![ScopeProjectPPMCNumber]"
... Where [ScopeProjectPPMCNumber] = " & Form_NewScope.ScopeProjectPPMCNumber
... Where [ScopeProjectPPMCNumber] = " & Forms("NewScope").Controls("ScopeProjectPPMCNumber")
You cannot reference object properties using string literals (ie pasting query strings from query designer), you have to reference the object properties (values) directy and concatinate then into the string.
Second you have declare an ADO recordset, so it need instantiating ie
Set rst = New ADODB.Recordset
needs adding before it is opened.
And finally opening a DAO recordset uses different syntax to a DAO recordset ie