The wallet bugs weren't fixed until after the attack. Livecoin was using the most up-to-date wallet at the time.
https://cointelegraph.com/news/monero-reports-on-resolving-fake-xmr-minting-bugs-a-month-after-fixBesides, the MIT license only pertains to Monero being able to absolve themselves of legal wrongdoing. No legal claims were ever filed against Monero by Livecoin, as far as I know.
When someone broke in to your house and stole your TV and you yell to them I will call the police!, do you consider it a threat?
Judging by the reasoning of the livecoin representative, this should be considered a threat

Your analogies suck. First you were claiming that buying a shitcoin that couldn't be withdrawn was the same as being out of gas in the middle of the desert. Now you're claiming that not being able to withdraw the shitcoin is the same thing as a robbery... You're being overly dramatic about a situation that was at least in part your fault. You should have done a better job monitoring your investment while it sat on an exchange for a year.