He can't just run away. Also he's afraid of when the prompt pops up he might accidentally press yes since it pops up in inconvenience times.
Idk if we're reading the same thing but your all questions and suggestions are answered already in the chapters with the reason why he can't do that!
First it was mentioned in one of the recent chapter that whenever he comes near any of the possible leads, their routes selection comes up and not once but many times so Jerry is just afraid that he might select yes either in them appearing suddenly or in panic! And that's making him scared!
Also yes he can run away but there were moments shown like that too when he avoided Every event yet the event with karyan popped up suddenly and way before it's time! So he can't run away from the plotline! And the bonus events he did, npc the hooded guy told the same he has to do what he's been doing aka following the plotline!
does he not realize he picks the route? If he wants to avoid any romantic routes he can just pick no. It seems like he unwittingly triggers events but he can also go away and avoid the whole storyline if he wants to based off of the time when he was sick and went away for a couple years.