Another, non JW or LDS answer is the historical grammatical hermeneutic. One tenant of this method is that the grammar and history of scripture will always confirm what it says in other areas. Scripture supports scripture

No, I did not create this approach at all. It is the approach taken by Jehovah's Witnesses who started out by questioning beliefs and looking directly at the Bible to figure out whether a belief was Biblical or not. That's how they came to the conclusion that hellfire is a lie and many other things that the Christendom accepts aren't actually Biblical. It's a very balanced approach. It also avoids all the "God hates $group" garbage and gives solid reasons for what's going on in the world. If you want to learn about that method of Bible study, check out jw.org.

Ironically, the name "Jehovah" is a misunderstanding. It comes from applying the vowels from "Adonai" (my lord) to "Yahweh" (the name of God).

The Hebrew alphabet initially didn't have vowels, so the name was written as YHWH. When vowels were introduced they decided to write the vowels for Adonai above YHWH, to remind readers not to say his name, as it was too holy. Eventually people forgot this logic and assumed it was the normal spelling of his name.

Even so, it's the most recognized way to pronounce the name in English. Yahweh is also acceptable, but isn't as widely used.

The funny thing about it is that we also don't know how Jesus' name would have been pronounced for the same reasons, but nobody ever has an issue using "Jesus", but people say "Jehovah" and it causes a stir. ¯\(º_o)/¯

Well Jehovah's witnesses think it's important to use the personal name of their god, so it's a bit amusing that they get the name wrong. It's like they fell at the first hurdle.

To be fair, the mistranslation predates them. I see they acknowledge the issue and think it doesn't matter.

I guess it's a bit of a coordination/communication issue with other JWs and with the world at large. The fact that they stick with this mistake doesn't mean that individual Witnesses, or the group as a whole, are stupid, or don't understand their own religion.

From my understanding, this is the oldest approach to understanding scripture. To keep from deviating from the truth you must examine the text in light of what has been written before. Acts 17:11 bears this out, "Now these Jews were more noble than those in Thessalonica; they received the word with all eagerness, examining the Scriptures daily to see if these things were so."

This has always been a key approach to Quranic exegesis. I wouldn't be surprised if they were influenced by Islam when it comes to this topic. Of course, Islam also has very rich bodies of information such as Hadith, and authentic quotes by the Companions and the Righteous Followers, all of which are used.

I would recommend getting the Ancient Faith Study Bible, which uses a very readable translation, and has extensive footnotes that consist of commentary on the Bible from the Early Church Fathers.