This is a seemingly known issue when delivering email to Google users: Google changes any \"height\" declarations to \"min-height\". This means that images that are stacked
I had DIV tags that I was forcing to be display:table-cell
I resolved this by adding a 1px wide spacer image into the "cell" with a height attribute (not css style) set to the height I wanted the cell to be. This isn't ideal but got the job done and is cross-browser/email client.