Actually, all you've shown is they may have used it, but simply out of necessity, such as for "word processor capable of Arabic in 1997" (your own previous quote). It is altogether another thing to be a supporter of something, an outspoken advocate, as communist governments are of Linux. They even have their own versions, your shakey evidence that terrorists may have merely used Windows in no way compares in magnitude to entire governments like China, Cuba, Venezuela, North Korea, Iran, etc. backing Linux. To even claim it possibly could shows your dishonesty.
They did use it. Windows, the operating system choice of terrorists.