Detailed Explanation
Pillaged! implicates the following three laws.
1. A bailee may not be negligent in his/her duties and is consequently liable for damage, theft, or loss due to his/her negligence regardless of whether he or she receives payment for his or her services.
Failure to ensure that the trust is not easily accessible to thieves is deemed negligence; the particular guidelines for which depend upon the security risks and due expectations of the time and place [Choshen Mishpat 291: 18] .
(A bailee must even thwart off thieves [Choshen Mishpat 291:8], though is not required to risk his/her life while doing so [Choshen Mishpat 303: 3])
Example: Homes in Babylonia were generally not secured from thieves. Under such conditions, Shmuel the Talmudic giant ruled that the only responsible mode of guardianship for valuables would be underground. When conditions worsened and thieves began to tap the ground for hollow spaces, the rabbis required increased levels of security [Bava Metzia 42a, Choshen Mishpat 291: 15].
Conversely, in more secure environments, as long as the trust is not easily accessible to thieves, one need not bury the valuables in the ground [Choshen Mishpat 291: 18] .
2. A bailee would be required to duly upgrade his or her level of supervision commensurate with heightening security risks or else may notify the depositor in front of witnesses that he/she does not wish to continue safeguarding the article under the new conditions [Pischei Teshuva Choshen Mishpat 291: 6].
Example: Repairing B's lawnmower, A locked it in his shed with a standard Medeco™ lock. In the interim, the neighborhood sheds with simple locks suffered from a rash of break ins. A is required to move B's lawnmower into his alarmed garage.
3. A bridegroom is entitled to his dowry only following the nuptials[Pischei Teshuva Choshen Mishpat 70: 3].
Application
Moritz only receives ownership or the right thereof upon marrying Hanna. Thus, throughout the engagement, the money belongs to Hugo. Consequently, Hugo appointed Edwin a trustee over the funds.
Though Edwin took extra precautions beyond the norm, over his personal valuables even under peaceful conditions, we may assume that hiding the money in his locked safe beneath his bed was a sufficient mode of protection against thieves.
However, as a trustee, Edwin should have been alert to the changing security risks. As the facts proved, when mobs of marauders ransack homes, a higher level of supervision is required.
Thus, he was required to move the dowry into his underground vault or else notify Hugo in front of witnesses that he no longer wishes to safeguard the money under the new conditions.
Edwin's failure to relocate the money to the underground vault was a negligence on his part. Consequently, he was liable to reimburse Hugo the 25,000 franc.
Hugo remains responsible towards Moritz should Moritz go through with the marriage. Thus, irrespective of whether Hugo succeeds in collecting the reimbursement from Edwin, Hugo is required to deliver (a new) 25,000 franc upon the marriage date to Moritz upon his marriage to Hanna.
[Answered by The Fellow-Yesharim Research Center]