"(a) Lessee agrees to maintain insurance fully indemnifying the Lessor from any damage to life or property which may occur on the leased premises and from any ... "

" .../tenancy_at_will_model.docInsured Risks: means the risks of loss or damage by fire lightning explosion ... 2.1 The Landlord lets and the Tenant takes the Property on a tenancy at will ... agreement and to keep the Landlord fully and effectually indemnified against all costs ... "

À la décharge de means that the burden of doing something (doesn’t rest)(no longer rests) on a party, that this party is (not)(no longer) required to do something.

Cf.
Au fig. [Le poids enlevé est une obligation]
a) [L'obligation est un dû matériel] (…)
b) Rare. [L'obligation est une responsabilité] Fait d'ôter à quelqu'un la responsabilité, la mission ou le soin de faire quelque chose :
... je remercie les personnes qui veulent bien tenir ma place dans ces fonctions et s'y faire mes intendants pour l'heureuse décharge que leur activité daigne me procurer...MAURRAS, L'Avenir de l'intelligence, 1905, p. 64.
(http://atilf.atilf.fr/dendien/scripts/tlfiv5/advanced.exe?8;...

Cf. also
« …to remove some of the burden placed on government social services…(=) …pour décharger les services sociaux gouvernementaux d’une partie de leur fardeau… »
Private Member's Bill - Bill C-239 - First Reading (42-1)
www.parl.gc.ca/HousePublications/Publication.aspx?DocId=812...

In AllegroTrans’s case, the Lessor is not required to be insured against glass beakage because the "contract" (?) provides that the burden of such insurance rests on the Lessee.

Would something like this work here: "He shall further insure against Glass Breakage risks, thereby relieving the Lessor (from any obligation?/duty? to do so) and without any possible recourse against the latter"?