They do have some flex, so if I tighten the elastic they should come in more. I did try putting the hair dryer on the thinner parts of the arms, but no luck there.
Will play around with the elastic, and then take some more pictures for you all!
Edit: Took some quick pictures with my phone after work.


When stretching the elastic and holding it with my fingers it seems to bring the sides in quite a bit. I'll have to attach the snap to be sure, but it looks like things will be ok after all 