God's Name in American Sign Language is symbolized by two letters, but I am not sure how God's Name is signed in Chinese Sign Language, since Chinese is built in a different way than English.
Jesus' name in ASL is not based on "letters" at all, it is a sign using the middle fingers of each hand to tap the middle of the opposite hands (formulated by somebody trying to symbolize where they think the nails were driven through).
I don't know much about braille, but I do know there are little dots poked through a page and that stands for different thoughts and expressions.
Languages are all about symbols. Whether those symbols are read/uttered/vocalized/acted/displayed/felt/etc is not as important as whether their meaning is conveyed/understood.
As already brought out, Jehovah knows the languages are all mixed up right now - He's the One who did the Babel language thing. Do we know what the Meaning of God's Name is and Do We Believe what it means? Do we call on Him in faith that He'll do everything He says he'll do and more? Those questions are more important than whether or not we say "Jehovah" or "Yahweh" or whatever. "Jehovah knows those who belong to him."
(Personally, I think it's easier to say "Yahweh" than "Jehovah", and I also think it's easier to pray through the name of "Yehoshua" than "Jesus", but I've prayed to God using both the name "Yahweh" and "Jehovah" interchangeably as well as praying in ASL at times using the name-sign of God as "J-H" and He's answered prayers when I've used any of those "pronunciations".)
I don't really care what the GB says about it, because the whole GB/FDS/exalted-clergy thing is part of "Babylon the Great" anyway. They make a big deal out of little things and then swallow down the camel. Jehovah has real witnesses in many religions, and some who don't belong to any religious institution.