Seems they use https://www.randompicker.com/ for picking the number.
But you should consider editing this statement
You qouted a part of the FAQ relating to dice, slot and blackjack. Results on these games are generated using seeds.
(Edit: We added a sentence about lottery in that part so users dont confuse the section for the single player games with lottery.)
However lottery works different. The "How is it played?" Section clearly stated that. We use a third party for the ticket picks instead of seeds.
As for randompicker.com, there will be a public drawing accessable for everyone to ensure everything was done fairly.