"my conclusion is that it must be the 2 movement revised version"
I'm sure you know this, but ALL of the three movement versions are 'hybrids' with the exception of Kent Nagano, who truly uses the first version throughout. In other words, "Waldmaerchen" was dropped from the revised version. I've never found an adequate explanation as to why Mahler dropped it. Did the text really change that much?
I'm new here, but have been a Mahler devotee since the time that there was only one recording (Walter) of the 1st!
In answer to Barry, my own view is that the first part is musically inferior to the other 2 parts. It keeps starting and stopping between the stanzas of the poem. I remember discussing this with Pierre Boulez (name-dropping I know) in the late 1960s and that was his view. So, unless he changed it, his new disc is probably of the revised version.
There are a lot of changes to the orchestration of parts 2 & 3 in the revised version, (I suspect for the better) and one whole passage has been rewritten, which is a bit of a shame as it is quite weird in the original - polytonal and polyrhythmic. I don't have the Nagano and it's now unavailable except at a gold-plated price from Amazon.
Hope this helps.