Leather Masters Cleaner and Strong Cleaner is in my Shop and it works good on dirty spots..
I also have a collection of little leather brushes with those light colored tampico bristles..
They work and get the product into the valleys of the leather grain..
I remember once seeing a video of Jack, the man that used to own classic motoring accessories a few years ago, taking one of those little brushes to some leather and scrubbing the heck out of it.
He said he once took a leather coat or something to a leather shop and the owner did just that to the leather coat...
But, as has already been said, you have to really either know leather and the coatings it may have or be really careful that you dont hurt something...
The leather masters people used to have a guy - a real leather guy who would answer questions for people about anything that had to do with leather, coatings, etc., and wow, it was a real eye opener to see how many ways leather is treated, coated, etc., after the tanning process... Way too much information but still needed for those who work with auto leather seats all the time like me..
They sell some Leather Masters products here but they also sell them on Amazon..
From what you and RonK have indicated and from the pics I have seen, it appears to me that these products really coat the surfaces and dont necessarily want to come off - regardless how good or bad they look..
And CarPro makes NO Cleaner/Remover for their products ???? Unbelieveable...

I have never used them and now for sure I will never use them..
Good luck !!
Dan F