Yes, quite likely everything was working OK... but there was just a timeout between Bitcoin Core and Armory so you got the weird error about the transaction not being able to be sent OK.
Then, after you cleared everything... and tried to send again... you get the "mempool conflict" error, as the coins have already been "used" in the currently unconfirmed transaction.
I would say that your current options are:
1. Just wait... your transaction will either confirm, or after 14 days is likely to be dumped by the majority of nodes and you should be able to create a new transaction (with an appropriate fee!
) and send that out without issue
or
2. Attempt to accelerate the transaction using
the free ViaBTC accelerator (assuming your transaction fee rate was >= 10 sats/byte). It's hard to get one the 100 hourly slots tho... you have to send within the first second of a new hour (ie. when the clock turns XX:00!) or you'll get "submissions beyond limit" which means the 100 slots have been filled.
or
3. Check if the transaction on the block explorer is marked as RBF... blockchair.com and mempool.space show pretty clearly whether the transaction is RBF or not... if it is RBF, you can attempt to broadcast a replacement transaction that bumps up the fee... however, given the error that you are getting, it seems like it might not be RBF enabled