i must've not triggered gman to walk away because i don't think i was supposed to climb the airboat

yeah i just realised that could be it. i had this issue when testing the ep2 cutscene since it was a chore getting it set up. the game'll just save things as they are in that moment and not adjust them to accommodate addons being enabled/disabled.
oddly, that's not one of the edited maps. the only hl2 maps that were edited are the intro (d1_trainstation_01), the start of route kanal (d1_canals_01), and the ending (d3_breen_01).

after the gunship fight right before black mesa east, i parked the airboat near the gate, jumped on it, and saw King just.. chilin. disabled the mod, loaded the save and saw gman collapse. I think this happens because you adjusted the maps for this mod.

@Kiwi don't see why that would happen. any other mods you're using?

so uhh... disabling this mod causes gman to collapse