Tuber this is a very negatively biased site against witnesses with information that your relative will realise eventually where you are getting it from because a lot of these are not very original attacks on witnesses. Jehovah's witnesses are a well respected mainstream religion something this site will not make clear. Steve Hassans books are not about main stream religions like Jehovah's witnesses.
You have done some research I see but it is very basic as well.
While "yahweh" is the most modern hebrew version of "Jehovah it would be odd to use "yahweh" in a bible when all the other names are transliterated into English who normally happily using the English "J" instead of "Y". Yeshua is the closest hebrew way of saying the English "Jesus" but we don't use that. So using "Jehovah" which is in the KJV psalm 83:18 and is the established and oldest English transliterated version of YHWH is perfectly fine.
Ancient hebrew was originally a vowelless written language, the consonants serve as sounds for vowels too. People would read YHWH and know how to pronouce it with just them letters. So YHWH is the whole and original name for Jehovah in written hebrew. The addition of vowel points to the original language was much later about 500 years and not always indicative of the original pronouciations. The Jewish superstition on Jehovah's name was not shared by early israelites and Jews who used it nearly 7000 in the hebrew scriptures and in psalms to be sung. The eventual removal and superstition on Jehovah's name was because of a misreading of a commandment in the bible about not blaspheming on God's name which they took to mean not using it at all. Jesus openly condemned this practise saying he had to "make his father's name known" to them.
ASV and NIV are both good translation but they do suffer from adherence to trinitarian theology and directly reflected on how they were translated. NWT is acknowledged to be an accurate translation.
Replacing a name with a title either "lord" or "God" 7000 times really adds to the inaccuracy of modern bibles and in fact led to indirectly to the confusion between Jesus and his Father Jehovah who both hold the title "Lord" which then helped lead towards the false teaching of Trinitarianism.
When someone personally gives you their name to use it shows an intimacy of friendship that the more formal use of titles lacks. Moses was accounted as Jehovah's friend so Jehovah revealed his personal name to him and as his people we also get that honor. When the jews rejected God's name they lost that intimacy of friendship. The bible is very clear Jehovah's people would use his name and come to know him personally and deeply.