This looks like the "Outlook Page Break Issue". It is one of the quirks of the Microsoft Word engine that Outlook uses to render html. It adds an invisible break line in there, and if you have anything too tall (like an image) it will bump down. Unfortunately it is unavoidable, so you just have to design around it.
Good news for you is that your sections are rather small. Try adding or removing 30-60 pixels somewhere in your design above the trouble area. The break point would then fall above or below your image, preventing it from being pushed down.