Mhh. I don't want to condition your choice, so I am just going to post you two very useful links to use when you are uncertain on how to build a pokemon.
1. https://www.serebii.net/potw-xy/059.shtml
2. https://www.smogon.com/dex/xy/pokemon/arcanine/
You can check here for all the items in game: https://pokemonrevolution.net/forum/viewtopic.php?f=89&t=11962
Razor Fang, hold by Gligar, Murkrow (Desert Lagoon).
You are not the first and you will not be the last to face this.
This bug can happen and there is nothing that can be done to fix it, so sorry, but you have to find a new Pineco. Staff always advise to make a pokemon evolve a couple of level before 100 in order to have a second or a third chance to evolve the pokemon again in case of bugs.
Sorry for the inconvenience.
This may be helpful, because there are a lot of moves and abilities bugged or not coded yet.
https://pokemonrevolution.net/forum/viewtopic.php?f=98&t=27264
I think it will be better than the sevvi island: that archipelago is small and with nothing to do actually, while the orange islands are larger, so I expect those to be a custom region with 8 badges, elite four, etc.