Various (newer) Armbian OS images do not have a separate boot partition (anymore). So there is then only 1 partition where also the DTB files are and it is Ext4 formatted, which Windows cannot read. So you need a Linux computer to do DTB file copy.
You might encounter another problem, as usually a DTB file is paired with a matching kernel/version, but I do not know your files/version/images, also have no Amlogic box.
Elton Sousa reacted to eselarm in Boot partition not showing on windows after burn images to sdcard