Dynamic Spectrum Sharing (DSS) is increasingly promoted as a central element of modern spectrum policy, driven by growing demand from commercial wireless systems, perceptions of spectrum underutilization, and advances in sensing and spectrum access technologies. Passive radio sciences, including radio astronomy, Earth remote sensing, and meteorology, operate under fundamentally different constraints. They depend on access to exceptionally low interference spectrum and are uniquely vulnerable to even brief or intermittent radio frequency interference (RFI). In this white paper, we examine whether DSS can offer meaningful benefits to passive services, or whether it primarily introduces new failure modes and enforcement challenges that undermine reliable protection. We introduce the concept of "just-in-time quiet zones" (JITQZ) as a targeted mechanism for protecting high value observations within dynamic spectrum environments, and we assess hybrid regulatory frameworks that preserve static protection for core passive bands while allowing carefully constrained dynamic access in adjacent frequency ranges. We analyze the limiting role of radio frequency propagation uncertainty, electromagnetic compatibility (EMC) constraints, and the current lack of comprehensive spectrum situational awareness. To formalize these challenges, we develop a game theoretic framework for DSS for passive services. We show why non cooperative sharing fails in "one shot" settings, identify the conditions under which cooperation can be sustained in repeated interactions with imperfect monitoring, and examine incentive mechanisms such as spectrum credits, penalties, and pseudonymetry-enabled attribution that can shift behavior toward compliance. We conclude that DSS can support passive radio sciences only when treated as a high reliability, safety critical system. Static spectrum allocations and permanent quiet zones remain indispensable for the most sensitive observations. Dynamic access may be considered in extended bands only when supported by conservative propagation aware safeguards, robust EMC practices, credible attribution, and enforceable accountability.