Silver is in two places at once

[jamescastells]

Polished Crystal contains the same mistake seen in vanilla Crystal (not present in the original G/S):

In Pokémon Crystal, because Silver doesn't battle the player immediately after entering the Burned Tower, the player can enter the tower and speak with Eusine, and see that Silver is in the middle of the tower, waiting for the player. However, if the player leaves and proceeds to Olivine City, when the player arrives Silver appears there, exiting the Olivine Gym, and then talks to the player before leaving. If the player returns to the Burned Tower, Silver will still be waiting for the player there.

A solution would be to block the player's path to Route 38 until the Burned Tower event is solved.

[Rangi42]

The player walks around; he can too.

If you think it's unrealistic for him to go back and forth from the tower to the gym and back... well, why were you doing it? :P