From that what I've seen in the code, all extern variables they are placed in bot_gloabals.h, they have to be placed also in bot_globals.cpp. Isn't here the same situation - if extern const bool RecursiveLightPoint exists in bot_globals.h, maybe it shoud be also defined in bot_globals.cpp? The only difference is - in this case it is a const (not a variable). I don't have such case in the rest of code, so I cannot compare it with anything.
Another thing - I don't have other clasess in podbot mm code, so I'm completly lost with Your function.
I have completly no idea how classes variables should be declared to be seen from other *.cpp files and their functions. If i.e. there is a function FVisible in util.cpp, it's just enough to add this decalration below in bot.h:
bool FVisible (const Vector &vecOrigin, edict_t *pEdict);
But how it should be made for functions they are some members of a class?