That's actually a bug on some platforms dependent on where you interact with the ticket machine (I believe mobile only currently). On all other platforms the character runs right then straight into the doorway. Try buying the bus ticket from directly right or right under the ticket machine
This is on PC, and it happens when I buy the ticket from behind the machine. Regardless, I am saying either Pam needs to move right of the door instead (it's closer to the luggage compartments anyway), or the ticket machine needs some way to force the player out in front before it can be interacted with. Alternatively, the pathing for the player after buying the ticket should take it down and right until it is low enough to walk past Pam, but I think it would just be easier to move her waiting location because her path to that spot will be the same every time and not have to deal with any variable data like where the player is when he buys the ticket.