I'm glad to see you got it solved, however, there is one thing i wanted to clarify:
walletbroadcast => Make the wallet broadcast transactions
zapwallettxes => Delete all wallet transactions and only recover those parts of the blockchain through -rescan on startup
source:
https://en.bitcoin.it/wiki/Running_BitcoinThere is a big difference between the two: the option you used just makes sure your wallet doesn't rebroadcast your transaction. The second option (zapwallettxes) makes sure the transaction is deleted from your wallet, so it'll never be rebroadcasted (since your wallet simply deleted the transaction).
OH! Well, the destination address is my account at a BTC broker's, but this could even cause trouble.
Question: So as I used walletbroadcast=0 and RPC aborttransaction $txid, should I restart BC core
once with -zapwallettxes?