I think it's combined problem of rules and the game trying to coalesce several options that happen slightly after another into one 'Player, choose form this list of options' UI.
With Royal Carriage (RC) on the Tavern mat, I played Embargo and correctly no option recall the RC was presented.
With Royal Carriage (RC) on the Tavern mat, I played a self-trashing Farmers' Market and correctly no option to recall the RC was presented.
With Royal Carriage (RC) on the Tavern mat (#7656495 as Ingix), I played Mining Village and correctly the game gave me the option to trash it and the option to call the RC. However, once I had trashed it, the option to call the RC still existed and when chosen, resulted in (incorrectly) me getting +1 1 Card/+2 Actions.