Consequently, adi_rebuild_devicetrees.sh script fails.
Do the files associated with this version of the SD card live on the Wiki fileserver somewhere?
Unfortunately not. But what you can do is use the dtc tool to de-compile the dtb file into a dtc file. Some semantic sugar is lost along the way, but all of the information is retained and it is possible to make modifications and then re-compile the dts into a dtb after the changes have been made.
dtc -I dtb -O dts devicetree.dtb > devicetree.dts
dtc -I dts -O dtb devicetree.dts > devicetree.dtb
Retrieving data ...