Confusion regarding bitrate blog post and "original" files

Just reading through the bitrate blog post:
https://www.sexlikereal.com/blog/post/id/82-vr-video-bitrate-explained

It states "For each file at SexLikeReal we provide the original file (also called the “Master” file) which is obtained from the studio using constant bitrate, and a transcoded version with the same resolution, but with a constant quality variable bitrate."

And it links to: https://www.sexlikereal.com/scenes/gabriella-lati-bed-game-5814 as an example where the original file is 3.31gb however there's a 90FPS file which is 3.82gb. If the original from the studio was 3.31gb how is there a 90FPS transcoded file with a larger file size?

Another example: https://www.sexlikereal.com/scenes/anal-virginity-6486 where there's a 10.35 GB original and a 11.24 GB transcoded.

Is this due to the default transcoder used? Would I be better of downloading the original file in these cases?