Prova così, ma non ne sono sicuro

Private Sub pVai_Click()
Dim VerbaleScelto As String
VerbaleScelto = ComboVerbali.Value
Dim vbaObj as Object
dim Form1 As Form
For Each vbaObj In ThisWorkbook.VBProject.VBComponents
If vbaObj.Name = VerbaleScelto And vbaObj.Type = 3 Then
set Form1 = vbaObj
Form1.Show
End If
Next
Unload Me
End Sub