AR Quick Look not always opening file

I've noticed sometimes that even on iOS devices with AR Quick Look, the browser displays the file as text instead of opening as 3D.
I'm curious to know how widespread this is. Have tested on several devices of different sizes, but there seems to be no correlation between phone (iphone5, 6, 7, X) and when the player does this.
There is a test page here, but is appears to be regardless of usdz file. Also on the page an image of the unexpected output.
https://lifetime2.unicaster.net/ar/kalinka.html

Anyone that has time to test, a solution, theory or other experiences, it would be much appreciated.
I'm wondering if it could be a memory issue, or a MIME type, although that would consistently cause the error, right?

The model is a convertion from GLB in the Reality Converter.

I had the same issue here. I hope someone could help.

AR Quick Look not always opening file
 
 
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