So as I see it, the error was that the file is not named the same as the texture folder and the texture itself. Everything must have the exact same name.
I tried myself to make a harpoon gun or a crossbow but it wouldn't work quite well, the projectiles kept making explosion impacts without actual explosions and npc's would do dodges from that too, which only happened if damage was set to higher value than 0
I also wanted the bolts/harpoons to stick into surfaces but the sticky flag offsets the model and it wouldn't work properly with the rotation of the projectile model
@lenao I went ahead and made you that crib pardner. You can reach me on discord: stryker78.
I can send you the file using discord. I created the crib from the model you linked and put it on display at the beach in front of the shop next to the mask shop. You can use something like codewalker or mapeditor or whatever to place it wherever you want.
You can take his player_one files and rename them Franklin and then place them into addonpeds dlc and then create a new ped, Name him Franklin, set him as Male, and set him as a Stream Ped (True). And he should spawn as an Ped when you press L and select him.