I don't know if there's a bug at all maybe just some fluke in the setup of hummer?
Because when I do ./lgogdownloader --ignore-dlc-count --list-details --game "tales_of_majeyal" it does list both of the dlc and my backup folder on the nas (where I use lgogdownloader to backup my games) also has several versions of the dlcs in it's folder so I guess it's been working for some time...
(also on version 2.26 and also arch linux 64-bit)
Here's the output:
./lgogdownloader --ignore-dlc-count --list-details --game "tales_of_majeyal"
Getting game info 1 / 1
gamename: tales_of_majeyal
title: Tales of Maj'Eyal
icon:
http://static.gog.com/upload/images/2014/11/911af0d6372e478985f6472499902b7e62eba4fa.jpg installers:
id: en1installer10
name: Windows Installer, English
path: /tales_of_majeyal/pc/setup_tales_of_majeyal_2.9.0.11.exe
size: 350.1
updated: True
language: English
id: en3installer8
name: Linux Installer, English
path: /tales_of_majeyal/linux/gog_tales_of_maj_eyal_2.10.0.13.sh
size: 748.5
updated: True
language: English
DLCs:
gamename: tales_of_majeyal_ashes_of_urhrok
id: en1installer7
name: Windows Installer, English
path: /tales_of_majeyal_ashes_of_urhrok_dlc/win/setup_ashes_of_urhrok_2.5.0.9.exe
size: 31.2
updated: True
gamename: tales_of_majeyal_ashes_of_urhrok
id: en3installer3
name: Linux Installer, English
path: /tales_of_majeyal_ashes_of_urhrok_dlc/linux/gog_tales_of_maj_eyal_ashes_of_urh_rok_2.5.0.10.sh
size: 55.9
updated: True
gamename: tales_of_majeyal_embers_of_rage
id: en1installer2
name: Windows Installer, English
path: /tales_of_majeyal_embers_of_rage_dlc/win/setup_tales_of_majeyal_embers_of_rage_2.2.0.3.exe
size: 140.3
updated: True
gamename: tales_of_majeyal_embers_of_rage
id: en3installer2
name: Linux Installer, English
path: /tales_of_majeyal_embers_of_rage_dlc/linux/gog_tales_of_maj_eyal_embers_of_rage_2.1.0.3.sh
size: 303.2
updated: True