If that guy has a big enough set of "boots" ie linier amp it will get into everbodies speakers ,'puter ,radio ,tv ,it will get them all . That plus some wireless phones .The whole neighborhood will be up in arms about it if they aren't already .
The FCC regs on CB's used to be 4 watts to the final output which would rarely be 4 watts going out but something less than that .
If the interference was further away a band reject filter would work but it's so close it's actually not even going through the I F portion just directly exciting the speaker coils . I wouldn't be surprised if it doesn't bleed through with the speakers off .