Script command to click the 'send' button of Mail.app

Good morning, from VBA I created a script that works well: open Mail.app > show the new message window ready to be sent. The following script clicks the ‘send’ button and the message starts.
Now I ‘embed’ it in VBA in the same way I created the message (I attach here the VBA code) but this part does nothing, the message window opens but the send command is not executed. Maybe I did something wrong referring to a window that remains open but on the second level below the Excel one. I use Excel 2016 and OsX El Capitan. Thanks to anyone can help me to understand, Massimiliano

APPLESCRIPT
–script that clicks the ‘send’ button
set myObject to “Mikey mouse”
set sendButton to localized string “ToolbarSend”
tell application “System Events” to tell process “Mail”
set frontmost to true
tell (first window whose title is myObject)
tell toolbar 1
click (first button)
end tell
end tell
end tell

SAME SCRIPT EMBEDDED IN VBA
Dim script As String, obj As String
obj=“Mikey mouse”
script = script & "tell application " & Chr(34) & “Mail.app” & Chr(34) & Chr(13)
’ code to create the message
script = script & “end tell” & Chr(13)

script = script & "set myObject to " & Chr(34) & obj & Chr(34) & Chr(13)
script = script & "set sendButton to localized string " & Chr(34) & “ToolbarSend” & Chr(34) & Chr(13)
script = script & "tell application " & Chr(34) & “System Events” & Chr(34) & “to tell process” & Chr(34) & “Mail” & Chr(34) & Chr(13)
script = script & "set frontmost to true " & Chr(13)
script = script & “tell (first window whose title is myObject)” & Chr(13)
script = script & “tell toolbar 1” & Chr(13)
script = script & “click (first button)” & Chr(13)
script = script & “end tell” & Chr(13)
script = script & “end tell” & Chr(13)
script = script & “end tell” & Chr(13)

'MsgBox script
On Error Resume Next
MacScript (script)
On Error GoTo 0

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