I'm unsure how an accelerator is supposed to help with playing BF6, but from the bit I was able to learn about accelerators it's possible the way yours operates may be against EA ToS.
About your account getting hacked, then your only real avenue there is to ask if the time in question they detected hacks came from your IP. If your accelerator uses proxy connections (since you're talking about nodes, I assume so) then that argument goes out the window because you won't have a consistent IP connection.
Don't threaten people with "legal action." You're far more likely to anger someone with those threats, and when they're angry they'll work against you instead of helping. EA ToS likely covers everything down to "we can ban you because of any reason we say" so you'll lose anyways. EA was bought out by the Saudis as well, so you know, good luck.
I'll also say this. Javelin doesn't catch many cheaters, but it does catch cheaters.