As my old apprentice master would say “…aye, experience, one thing ye canny buy in the shops…” and how true..
Having obtained several more very high resolution spectra of varying kinds it suddenly occurred to me what was going on with this one.
I was also pretty sure that there was an order division but as I was expecting the distinct pattern of atmospheric near IR emissions toward the right of the spectrum, the lines present threw me off track a bit, However your division there was spot on. The issue seems to have been I bumped the focus! When this image is compared to my later ones it is clear this is the case.
Also, one of the other secondary pieces of information that can be gleaned from the spectrum image is that since the 2nd order are so clearly present it indicates that the meteor must have been a slow one. (As well as being rich in Fe lines!) Otherwise these lines would have been overlaid or masked by the pattern of near IR emissions from the atmosphere.
A bit rough and ready but it now all makes sense. Another mystery finally resolved!