Both are non-canon ships, and both require authorization from CBS and acquiring the rights but this is were the difference starts, in relation to the Vesta is just one person as the Typon is a now defunct developer and a publisher.
I am not sure were CBS would stand with the Typhon, my guess is CBS simply does not to use ships from other games because it muddles the waters, the moment you let the Typhon in you also let everything else from the Invasion game in.
grylak, its not a matter of the way its built adding hull strength, its a function of the ship being very small. (Its probably about the size of on the the Atrox's wings, if I had to eye ball it. Might even be a bit smaller.) The smaller the ship means, while theres less hull to reinforce, theres less hull over all. I dont see the Typhon having a hull strength over at most 35K.
I see it as although the Typhon may not be a particularly big ship, it has a thick hull (much thicker than normal ships) to help reinforce it while in battle and the design of the ship. That would increase it's hull strength. But that may not be how hull strength is done in game. In fact, in game, it probably is done purely off it's size. In which case, it would have a lower hull strength.