Talk about making up your own theology. You take several things for granted. First, there are multiple spellings of many words in Hebrew. What makes you think the two you give are mistakes and not other words or variant spellings? If the missing letters are mistakes, there is no reason to believe they were done intentionally instead of being accidental. You cannot make rules from exceptions when it defies every other rule, including common sense.
No one is making up a theology here. The text literally says:
זה שמי לעלם
Which can be literally read "zeh shemi l'elem," or "zeh shemi l'olam" -both and. Not either or.
It means both "this is my name to conceal"
AND "this is my name forever." We have the responsibility to accept both understandings, and not exclude the other. In the Torah scroll, there are no vowels (which literally translates this phrase to "my name to conceal"). What we have as far as how to read it, is what is handed to us by tradition in the pronunciation of the words, which is part of the oral Torah (which literally translates the phrase to "my name forever"). I don't pick and choose between what is literally written in the Torah, and what is oral Torah. I accept both.
The original inspired Hebrew dictation of the Torah had no vowels - not just because vowels weren't invented yet, but because the Hebrew of the Torah is multidimensional, so as to give additional meaning to the text beyond the face value or what is passed through tradition as the oral Torah. After all, we learn that there is more to the text than just what appears at first glance, or even second glance, from even the very first letter of the bible... the oversized bet - which teaches that we are to ask of even every letter why it is the way it is. That the heart of Torah is derived by asking questions of it. It is not adding to the Torah. It is letting the Torah explain itself. There are of course limits, but this post and thread is not to discuss what those are or what the rules of Torah hermeneutics is.
The phrase in question is literally spelled in the Torah in Ex 3:15:
זה שמי לעלם
which literally is "zeh shemi l'elem" "this is My Name to conceal." It is only from the oral tradition, the oral Torah, that we learn to read it as
זה שמי לְעֹוַלָם
This vav is missing in every single Hebrew Torah text in existence. Unless you don't believe that G-d's word is preserved in every generation, the Torah we have today is the Torah that Moshe wrote. Every intentional mispelling, grammar error, missing word, empty space, yod, tagin, half sized, oversized, reversed letters, in the Torah - is for a purpose. To give us a self-extracting archive of the Wisdom of G-d in how to love G-d and others.
This vav is missing not because it's a mistake. But because it's on purpose (we must assume so, or else we must call into question the integrity of the Word of G-d as handed to us). The vav is missing from what is read, not from what is written. It is read l'olam, but it is literally spelled l'elem. To ignore that it is written l'elem is to subtract from the Torah.
I choose to believe what is literally written here. His name is to be concealed. This is a clear Torah prohibition. In fact, the very idea that one reads
לעלם one way when it is written another, teaches one that one must also do the same when it comes to G-d's Name, the tetragrammaton. This is not a made up theology. This is what is obvious from looking at the Hebrew of the text itself. To not accept it, in my opinion, is what
would be making up a theology, or in this case, ignoring it.