Images squished on .rtf compile

I have a bunch of images (~100-150) in my manuscript. 40 of them are very similar, and all of those (and only those) are squished (so they’re normally sized up and down and half size horizontally) when I compile to .rtf and open in Microsoft Word. Any idea how to fix this aside from manually changing the proportions of each one in Microsoft Word every time I compile? The problem images are not the widest ones in my manuscript, so I don’t think it’s that…

I just made a test document and put in one of the problem images, as well as a copy of the exact same image made using a screen capture. The copy had no problems, the original was squished. The original was copy/pasted directly from Omnigraffle Pro.

Here’s the test document and the compile:
Archive.zip (127 KB)

In my fiddling, I’m noticing that if I right-click on the original, the contextual menu that comes up treats it as if it was text (has an option to “Look up XX”, where XX is a small rectangle with a dotted line border that says OBJ inside, which I assume stands for “Object”), whereas the contextual menu for the screencaptured copy is treated like a picture. (Has scaling options, etc)

Edit: Copying and pasting into google shows that the text is:
Unicode: U+FFFC  %ef %bf %bc OBJECT REPLACEMENT CHARACTER