Sorry, Bungie will not restore any lost or deleted items or characters for any reason.
[url=https://www.bungie.net/en/Help/Article/12211]Deleted item and Character policy[/url]
then Bungie should really add another step when deleting a character.
For example, Guild Wars 2 makes you type your characters name when you want to delete.
Could really just be a "are you sure" window ...
I kinda feel betrayed by Bungie here. They could at least make the boosts on a shared inventory slot with all your characters or something ... would mitigate issues like mine
They do ask you to confirm when you choose to delete a character.
You ignored it, and did it anyway.
And, you should have put that stuff in the vault if you wanted to share it between characters.