You can see what appears to be a part of the word Heritage on the COA behind he photo. If the auction house name is on the cert, then it is an auction house COA. It is my understanding that means it has had a cursory, but not full, review.
In my opinion, this signature is likely authentic, but it is not the best example. I would typically pass over an atypical signature in favor of something that can't be questioned.
I like most of what I saw, but the tail at the end of the second "M" is a little strange for me. I agree with your opinion. I would avoid this example also for the same reasons probably real, but very atypical.