Do seamless gutters have a 3rd piece?
Your gutter is seamless due to the process of metal forming as it comes off the machine in the truck. However, it is only your gutter that is seamless, much like seamless aluminum siding. You have to have some connections in all guttering and it is not uncommon for a very small leak to occur at the junction of the connections. If you can reach it, just caulk the seam with a silicone waterproof caulk to stop the leak. The only way I can see a problem is if the leak gets to your fascia board, and that would take a long time or a large leak with lots of rainy weather to cause some issues with that if the board is in good condition. And, your guttering person would have told you about bad fascia board since he doesn’t want to have to attach new gutter to bad board.
