Another YouTube video has been found with the title "And with this fire I purify", in it the words "sedm" and "dva" are repeated, and these are Czech words for Seven and Two.
There is a website out there called www.27project.org that epithetalpha has also tweeted about "This site means a lot to me: http://www.27project.org/" but it has no obvious links to Lost or these new "clues" that have been appearing.
Another possible link to investigate around EpithetAlpha and one of Simeon Hobbes' latest tweets - "May the light of Jacob be with you all this day, as we celebrate musical Aegocerus." - A search on Aegocerus shows that it is an epithet of Pan, who is a character from Greek mythology.
The whole thing is increasingly being labelled as a fan based project with no official connections to Lost, but it does seem well worked out anyway.