No, code cards can only be redeemed once, whether that be in the Pokmon TCG Online or saved for later and redeemed in Pokmon TCG Live
Yes, this has all the same risks as other enchantment and aura based removal in that it isn't very permanent however that is generally less of a concern with the utility creatures
It wont take many turns before your board is too much for an opponent to deal with, just so long as you are sparing with getting your creatures into combat
Heres an example that caught my eye: Yikes, that Candelabra of Tawnos has seen better days
Don't waste your gems You receive a bunch of gems during the first few hours of playing Master Duel, but don't go spending them all at once
This card seems like a phenomenal card to add to any deck, but it is tricky to use