That image has clear angles on it just like the image I linked to from here. I drew a red line parallel to the actual lines that we see. There are clear angles, which I pointed out clearly. You can’t just wish those away.
It may be a piece of cloth of some kind to hide a hinge; I don’t know. It sticks up straight, stiff, and square when the lid of the casket is open, so it doesn’t seem like a drape. In any event, it should be there in all the views where the casket is open.
I would think that a casket lining would be fairly stiff satin, not soft chiffon. It also looks like it could be ruffled. That could certainly appear to create angles from a distance!
In the image from your website titled “Hundreds bid a fond farewell to Loretta Fuddy” you can see a hinge on the left side of the casket, just above your red line. The picture is not good enough to see if fabric from the other side is shielding the hinge from the viewers.
And, of course, the fabric shielding the hinge was probably adjusted when the casket was brought to the front of the church for the funeral service, so it could have differed in appearance from the viewing.
So, again, the same casket. And certainly not a non-existent 2-tier casket!
(For someone so proud of her research regimen, you didn’t even do any research on caskets, did you? You just made up the idea of 2-tier caskets then stated it like they actually existed.)