My question is, can I take Poloniex to court?
This would depend on how exactly your account was hacked, was it a breach due to an error on your end or was it from poloniex server. If it was from your end then suing then would likely not yield much. Such services use their ToS to indemnify themselves in such situations, one of such terms;
Polo will not be liable for any loss or damage arising from your failure to protect your Account or your User information.
Source:
https://m.poloniex.com/terms/how can i get my funds back from US law enforcement given they have seized some funds.
If your funds were stolen from the indicted scammers, then you should consider seeking professional legal advice on the next steps to take.