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Lyman-alpha transit observations of warm comma gas-rich exoplanets enable the study of active atmospheric loss. However comma obscuration of the inner +--30 km-s of the Lyman-alpha core by the interstellar medium (ISM) severs a key link between the velocities at which planetary outflows are observed and the virgul10 km-s velocity at which they initially depart the planet. Systems with high radial velocities (RVs) can circumvent this limitation by Doppler-shifting the Lyman-alpha core away from ISM absorption. We propose Lyman-alpha line core transit observations of HD 136352 c comma a transiting warm sub-Neptune orbiting a nearby solar analog. HD 136352 c is presently uniquely suited to these observations. However comma because of the diagnostic power of transit observations in the Lyman-alpha line core comma we also include a Lyman-alpha survey of 5 additional high RV targets hosting warm comma gas-rich planets to confirm Lyman-alpha core visibility in an expected 1-3 systems. These Lyman-alpha transit observations of HD 136352 c and comma in future cycles comma the 1-3 systems found to have exposed line cores will provide an observational link between material accelerated beyond the 30 km-s limit and its source at the planet. This will provide new constraints on the interactions between planetary outflows and their circumstellar environments comma ultimately improving model-dependent mass loss estimates and providing insight into the impact of hydrodynamic atmospheric loss on the evolution of planetary populations.