I'm not going to comment on any of the actual drama; I just want to clarify a fact.
You can't dos someone who isn't hosting something, and if someone is hosting something you already have their ip
DoS stands for "Denial of Service", and it's a form of attack where garbage data is spammed to a target "server", in the hopes that the garbage will interrupt and suspend networking services for the target either by crashing or simply flooding the network devices on the target-side.
DoS attacks can be performed against anybody who is connected to the Internet, regardless of if they're acting as a web-server or as just a client, so long as you have access to their IP address, as that allows you to directly communicate with their networking equipment. There are, in fact, many web-services which you can pay to flood a specific IP address, which should usually be a server but could just be an individual's computer.
There's no difference between a device acting as a server and a device acting as a client in terms of IP, outside of the fact that most web-servers use static IPs while most clients/users have dynamic IPs, but technically you can ask your ISP to switch your account type at any time.