Your initial reply, now edited, asked how to put the image at the top of the email rather than the bottom. Maybe you've worked it out, but for the benefit of others here's how.
Replace:
'Find HTML body closing tag and insert embedded image reference before it
p = InStr(HTML, "</body>")
HTML = Left(HTML, p - 1) & "<p>The embedded image is shown below.</p><img src='cid:" & imageFileName & "'>" & Mid(HTML, p)
with:
'Find HTML body opening tag and insert embedded image reference after it
p = InStr(HTML, "<body>") + Len("<body>")
HTML = Left(HTML, p) & "<p>The embedded image is shown below.</p><img src='cid:" & imageFileName & "'>" & Mid(HTML, p)
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