Unfortunately, this isn't an issue anyone at EA Sports will be able to help you with. You'd likely need a networking specialist to come to your place and help you determine the issue.
Judging from the actions that you've taken, you've done everything you can on your end (besides replacing the modem but if you're getting the correct speeds that your ISP advertises then the modem is likely fine). Typically, with issues like this, upload speed is a big culprit. "Input lag" (which is what you and I and others experience a lot of the time) is usually determined by upload speed -- but yours are seemingly fine. You have 30MB UL which is probably above average for most ISPs. I know mine (Spectrum in LA) really skimps out and only offers 15 UL while DL is 500.
You said that your ping is 20-30ms, so you're generally close to an EA HUT server. Have you measured 'jitter' or 'packet loss?' If you're not seeing spikes in ping, you likely aren't experiencing packet loss. I'm sure you've already considered this but are you ensuring that your network bandwidth isn't congested while playing NHL?
Sorry that you're dealing with this. I don't play HUT but I get the same issue in WoC (which also uses dedicated servers). I assume it's because most of my opponents are NOT located close to me (being a chel fan in LA is rough) so I'm forced to play on servers that are further away.
The last thing I'll say is that I CONSTANTLY deal with input lag when playing online versus as well. As you know, online versus uses peer-to-peer hosting so it's a bit of a different animal. Depending on my opponent, games can range from SUPER smooth (if they live in LA) to straight-up RED connection quality. The strange thing is that I sometimes get the same issue that you're describing: a 30 or less ping game that somehow still feels sluggish like it's a 90 ping game.