The charcoal canister has nothing to do with EGR, nor does the carb. The charcoal canister's main purpose is to absorb/store excess vapors from the fuel tank rather than venting them to atmosphere.
EGR, as stated above is exhaust gas recirculation which is used to reduce NOX emissions or oxides of nitrogen from lean air/fuel mixtures.
The vacuum line on the dash pot would likely have been for activation, like when certain criteria are met, a vacuum supply would pull on the dash pot allowing the exhaust gasses back into the intake tract. Not sure which vacuum source it would have been hooked to but I'd bet if you look there is something capped off somewhere close that was supposed to go to that EGR mechanism.
You could also have a replacement engine or something with later equipment and somebody just didn't bother with all the hook ups.