If you were lucky enough to receive a reply from EA support (check this forum for how unlikely a scenario that is) you will likely have been told the issue is on your end. If you're using a wired connection, ports are forwarded correctly to both the console and game, and you have little network traffic, you'll have arrived at the same destination as many many players and realise, EA games = very poor connection. This is a combination of factors such as EA's bizzare matchmaking, EA's laggy servers, input lag, profit over basic functionality, and a general 'could not care less' attitude.

It sounds like you've done everything possible your end but sadly EA will never admit there's a problem on their end. But hey, you can currently buy one of EA's biggest releases of the year, Anthem, for £5 on Amazon UK because after being one of the most eagerly anticipated AAA games of the year, EA did such a good job and it was so widely hailed as 'awesome' that it's now the cheapest PS4 game you can buy, just 10mths after release! Winning.