Hi Jan,
You raise interesting issues.
We must ensure that we do not impose our concepts onto the idioms of the past. For those Jews, a "name" was more than an appellation, it was the very being of that person. Hence the need at times to change a person's name (to "Israel" or to "Peter/Petros" - although he "petered out").
The be saved (whatever that means) by the name of Jesus could equally be understood as requiring one to live in accordance with that as a standard. The reality of course is that the "name" Jesus is a distortion of the original, which was Yeshua, and which in turn is Anglicised as "Joshua". Interestingly, this is the earliest recorded genuine Yahwist name.
Yes, the WTS does intrude its prejudices upon the scriptural texts - and everyone does that - but more fundamental to me is to ask them: Why have they accepted and adopted the Protestant's scriptures?
I provide one of their sources that shows which OT texts cited in the NT employed the tetragram:
See the second page:
http://www.jwstudies.com/Translating_with_prejudice.pdf
The other factor is that there were several versions of the LXX and the NT writers worked from them, some of which we no longer have.
Doug