That’s correct, it is a GeoTIFF (though I don’t need the geospatial metadata). I didn’t realize there was a structural difference, so thank you for catching that!
It sounds like this would be the solution I’m looking for when completely implemented, but for now I’ll stick with the approach of downloading the entire file and reading it in using the approach outlined in ArchGDAL.jl.
Thank you all for the help!