You have admitted in your earlier comment that "Cloudflare was helping keep his website up." You are saying that "Cloudflare helped keep his website up" does not logically imply "Cloudflare helped me run a DDoS network".
Even if you genuinely believe that, how are you confident enough that people generally share your interpretation of what constitutes help to call the statement in question "false"?
Following this, their ISP, their electric company, their server hosting location, and presumably their government (with their monopoly on violence) also helped them run a DDoS network.
What's next, is the landscaper helping run the DDoS network because they cut the grass outside so people can access the building better?
The most important factor to consider here is knowledge.
If it is the case that Cloudflare provided services to this website with full knowledge that it was a DDoS-for-hire service, which seems likely, this would significantly increase their culpability. This may also apply to the server host, if the server host directly worked with them.
I find it difficult to believe that the ISP, electric company, or government knew of the actions that this DDoS service was taking, and how their own actions benefitted them, since these entities are so far removed from the DDoS service. But if they did have knowledge of what was happening, of course they would be culpable to some extent.
I also disagree with the implication that we have to make a black-and-white judgment of "they helped" or "they didn't help". Depending on the extent of involvement, a third-party can have varying levels of culpability in the DDoS service's actions.
Even if you genuinely believe that, how are you confident enough that people generally share your interpretation of what constitutes help to call the statement in question "false"?