Welp, I couldn't put it where you had it because there were an abundance of cables there, so I put it on the opposite side of the card, and it seems to be holding just fine. I screwed it as tight as I could with my hand, so I hope that holds, but it looks far more level now. It was still at the same level of sag as before, but I feel more confident in its longevity now. Thanks again!
Great job! Glad it helped!