Just walk. You're obviously visiting this site because you're contemplating purchasing a ticket. So to you, I say - walk rather than take Megabus. It will take several days - sure, but it would be expediently more pleasant.
And dependable. You can depend on your two feet can't you? Even if you can't and even if they gave out after two blocks - they would still have worked more than the 12 some employees sitting aimlessly in the only square foot of shade on the block. Imagine waiting over 2 hours for a bus alongside 100 some other stranded passengers in the unforgiving pavement-fresh July New York heat, and then trying to get an update from the dozen or so Megabus employees, and being told "No one is answering the phone. What do you want us to do?" And then continuing their heated debate on who's going to walk 20 feet to a nearby hardware store to purchase a trash can for some reason.
Or fly! Or take a train! Sure, it may cost 100 times the price - but it will still be cheaper than purchasing a ticket on Megabus, waiting over two hours to only be told that the bus wasn't going to show up, and THEN having to purchase a plane or train ticket. I mean - you would think that Megabus would give you a refund after failing to provide you a service that you paid for, but you would be mistaken. I've sent 6 emails - and have yet to receive a response.
Or take any number of more reliable bus services. Take Vamoose, or Bolt Bus, or Grey Hound, or Peter Pan, or highjack a school bus.
But for the love of God, don't waste your time or money on Megabus.