Guild Wars 2

Is there any way to become vigil after starting as whispers? (etc.)

How about a way to use their teleporter, at least?

nope. you stuck. Start new alt and go whispers next time. That is what we did

I thought that might be the answer.

Just a small addition, you can use all three portals to get from fort trinity to their hq’s, but only the one from your own order’s hq to fort trinity.

I am considering that as a bug, I often am playing with people who picked different orders and it is crazy that we have to split up to get to fort trinity (and ye, we are all cheapo’s not willing to pay ;-) )