This is what Chris from Hallson's said about Touch of Class and Catherine:

"Touch of Class has to be one of the most popular plants here but I knew it wouldn't be too long before other named plants would come along that were essentially the same plant. Since Touch of Class is a patented plant there will always be a desire in the industry to find an identical clone so that you can name it yourself then propagate it and avoid the royalties.

Some years ago Hosta 'Grand Marquee' was introduced from Holland and it is actually a dead ringer for Touch of Class. Either the registration was wrong on this one or there was a mixup in the production process because the registration put it down as tokudama lineage, when it is definitely tetraploid tardiana. If I was a betting man I would put money on it being a mixup.

Now I see that there is another Touch of Class look-alike: Hosta 'Catherine'. It is registered as a sport of Halcyon, but again, it shows definite tetraploid characteristics. My guess is that someone had a tetraploid Halcyon that sported to what they named 'Catherine'."

You can read more at this link:

https://www.perennialreference.com/forums/viewtopic.php?f=1&t=53928

I think what Chris said makes a lot of sense. Also, I have also heard that many times new hostas are registered "in a hurry" before they are fully mature. That would make a difference to the vein count on registration.