I ran into that bug you mentioned and got locked in the room the first time I played.
I played it again but with a controller this time and noticed you can't progress dialogue with just the controller (pressed all the buttons), made it to the boss room, defeated the boss and the chest spawned this time and I got the bomb ability but all the coins that I hadn't collected disappeared in there and then the door closed and locked me in there. Tried to bomb my way out but couldn't so I guess it bugged.
So I started it for a third time with all this in mind and managed to get all the coins and the bomb ability, and move to the next level, was in the middle of defeating the boss there and got stuck between barrels and the wall, tried to use a bomb to get unstuck but died instantly.
Started it for the fourth time, coins and collected orbs somehow hadn't reset and I had the sword already, so getting to 99 coins was pretty easy, and since it hadn't reset my bomb ability either I could basically speedrun by not fighting the second boss and just bombing my way in to the other places, managed to finish in the end with 99 coins (since they hadn't reset)
I was a bit confused as to why when aiming the bow the aiming gets locked, and the movement speed could have been a bit faster or an option to sprint would have been good, but other than that there's a solid game here but needs more polish which is understandable since this is a game jam game (mine also needs more polish)