Toxic duo bot lane gets me permanently banned.

So this is the first time I've posted and I am posting here because of a permanent suspension on my account that I think is unjust and I was wondering what you guys thought about it. I've been banned before and have been improving my behaviour ever since then (which is why it was permanent) and I honestly believe this is the only game that I've actually been reported in ever since my un-banning.

So the story begins with me and a couple of mates playing a couple of games in League. My friend who is fairly new to league decides to try out ryze for the first time, he verses a mid lane garen and loses lane pretty hard but I don't really mind because he's my friend. He makes a few mistakes every now and then but no one really cares until he forgets to MIA ping Garen, who roams down to bot side and gets a double kill. This causes the bot lane duo to start flaming him consistently (keep in mind this was the first time he forgot to ping). At this point we are about 20 minutes in to the game and I haven't been toxic to either teams and was doing decent score wise. I decided to roam down to bot-side due to our adc and support roaming around the map. I run on over to bot side and try to get a kill on Miss Fortune which is then taken by Draven who flash's to take the kill which I didn't really mind considering it was a Draven adc but he quickly typed out "EZ". Now this ticked me off quite a bit considering how much they've been harassing my mate at mid (e.g spam pinging him for no reason, telling how to MIA, tell him he's trash and bad, etc)

So I tell him: Nito: wtf Nito: are you Nito: doing Nito: you Nito: useless Nito: adc Nito: Piece Nito: actually useless

Now this doesn't seem that bad to me, it was pretty harsh thats for sure but considering how much they've been feeding, taking our junglers camps for no reason, consistently pinging me and my friend about how we should "refund our skins and should "just give up hope" I think that letting out a bit of steam shouldn't be considered dishonerable. As unsportsmanlike as it is to call someone useless I think what got me banned is what I said after the whole draven flash fiasco was what I said to my friend (who I've known for quite a while) who wasn't in voice chat with me and my other mate (the ryze mid)

Nito: KYS I said this to my mate (the kayn) as a joke because of what he said to me In voice (He called me a bad gp) and directly after me saying that the Draven replied with "Oh telling me to cause self harm?" "report him (the lux's real name)"

In all honesty, I believe that my ban was pretty unjustified and wish that Riot support could actually investigate the chat and the other players before just banning someone because their system found a word that is bannable.

Heres the full chat list for those who care:

Game 1 Nito: ... Nito: i mean Nito: too fast Nito: -_- Nito: xd Nito: nah Nito: riven Nito: and garen Nito: wtf Nito: are you Nito: doing Nito: you Nito: useless Nito: adc Nito: Piece Nito: actually useless Nito: KYS Nito: good job Nito: 9 and 9 Nito: woo Nito: lol Nito: lol Nito: i dont need to Nito: ty Nito: nah Nito: whats he saying (I muted the draven and was asking my friend what he was saying) Nito: ty Nito: woooow Nito: bad luck Nito: what??? Nito: he can jump walls Nito: i cant Nito: in english please Nito: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA Nito: nah Nito: i like it (Tells me to refund skin) Nito: where the fuck that damage come from Nito: xd Nito: why? Nito: wouldnt that be giving up? (Lux support tells me to "Just give up hope GP") Nito: thats pretty mean Nito: thats pretty rude (Insults my friends and I) Nito: yawn