How do you clear default launch options on a Remote Play?

I mistakenly ticked the "Always use this option" box on a launch option which breaks the game. But I can't seem to find any option in the game's properties to now revert back to "Ask when starting game" on the client. The option is only visible on the host PC, which has already been set to "Ask when starting game", and it does just that. The client though just attempts to open the game with a broken launch option.

Is there a file in somewhere depths of Steam user settings where I can clear this setting?

I assume this simply not being visible is due to an oversight by Valve for when the game is not installed on a client, but you want to change the default options for Remote Play.