However, she ends up getting Hana kidnapped by men targeting what was kept in the safety deposit box. The kidnappers turned out to be detectives.
Literal
However, that safety-deposit-box [target-に] entrust-[progressive-ている] thing [object-を] targeted men [by-に], Hana [object-を] kidnap-[passive-受動されて-regret-しまう]. Those kidnappers [with-とは], actually detectives [copula-past-だった].
Complex crime-story narration. 誘拐されてしまう combines passive ('be kidnapped') with ~てしまう (regretful completion). 狙う ('to aim at, target') with past form used as pre-nominal modifier. Note とは at the start of the second sentence — here it's the definitional topic marker ('as for X'). Reads like a mystery plot synopsis.