As most of the time happens with an idea that sounds good to me, I do not see something until putting it together. I usually try it anyway because sometimes it leads to something better I did not think about until trying it. Splitting the parts apart around the EMT tends to push those parts away, so I gave up on splitting the middle joiner part. The EMT is still held in place quite well at the top & bottom & it does not move when I try to rotate the pipe. I did not hear any cracking when tightening the bolts this time. As you can see from the close up photos, it does flex the top & bottom plate, but since I am using PETG plastic currently it is working pretty good. Will see how it holds up over time. It was also a little more trouble putting all these pieces together since they had a tendency to go where they wanted to. I am probably only going to use 1 corner with that part for now.
Here are a couple of close up photos of it installed.