Go and read again.
https://www.icrc.org/applic/ihl/ihl...t&documentId=BE2D518CF5DE54EAC1257F7D0036B518
COMMENTARY OF 2016
ARTICLE 2 : APPLICATION OF THE CONVENTION
Text of the provision*
(1) In addition to the provisions which shall be implemented in peacetime, the present Convention shall apply to all cases of declared war or of any other armed conflict which may arise between two or more of the High Contracting Parties, even if the state of war is not recognized by one of them.
(2) The Convention shall also apply to all cases of partial or total occupation of the territory of a High Contracting Party, even if the said occupation meets with no armed resistance.
(3) Although one of the Powers in conflict may not be a party to the present Convention, the Powers who are parties thereto shall remain bound by it in their
mutual relations. They shall furthermore be bound by the Convention in relation to the said Power,
if the latter accepts and applies the provisions thereof.
I am not aware that LET and others has shown any acceptance of the Geneva Convention.
There is a further clause. Muslims, which believe that Martyrdom will be theirs if they die for Islam, are getting extra compensation compared to ordinary soldiers, and thus are defined as
soldiers fighting for their own prosperity.
That means they are classified as
mercenaries which has no rights whatsoever according to
the Geneva Conventions, regardless whether their nation has signed the Geneva Conventions or not.