The sources I brought up, except all the media group connected to niezalezna.pl, are also: wp.pl, rp.pl, uakron.edu, gazetaprawna.pl, sejm.gov.pl, naszdziennik.pl, stefczyk.info, videos on youtube and some others. I could also bring sources like uwarzamrze.pl, wpolityce.pl, wprost.pl, onet.pl and many others. But niezalezna.pl seems to provide the most of information on that investigation, the most detailed. You can always say they are political, right-wing, etc., and you can always call every investigation of any crime a “political game” because there is almost always someone who could benefit on it… But there is an interesting thing: If the Law and Justice party and all the “right-wing extremists” are pushing a fake-theory of an assassination, then why they are all demanding an international investigation on it and all the others are so afraid of it? What do they have to hide? Why the Law and Justice party runs the risk of an international shame and loss of all the voters support if it was really an accident? 
What you are trying to defend here is a theory of a ghost-plane flying under the ground, smashed by one of the armored birches that grow only in Russia… And you don’t say it’s a fringe, conspiracy theory, it’s an official, true version! Just because the terrorists ruling in Russia (responsible for many other political murders – will you deny that?) said so, because they led an investigation on it and the Polish government confirmed it and all the mainstream media repeated it and then all the international media repeated after them (what else should they do?). And the only other investigation with a rational conclusion with a hypothesis of explosions is a “fringe theory” that has to be removed...  Also one thing I have to add here: do you know anything about the war between Georgia and Russia in 2008 and the role of L. Kaczynski there? Do you know that he gathered four other countries leaders (Lithuania, Estonia, Ukraine, Latvia), went to Tbilisi and forced Russian army to stop the attack on Georgia? See:  Do you know there was already an assassination attempt on him right there, in Georgia? See: . Do you know that the Katyn_massacre was also a revenge? 
However, after all, I’m glad that you finally focused on merits and try to find some other explanation for the explosions, that about the fuel tanks. (then the official reports must be lies, too.) As I know, the fuel has to be mixed with air/oxygen in some proportion to explode, otherwise, with a surface-contact with air, it fires slowly. However, It is all to be investigate by an international commission. And, about the balance in the article, the only reliable theory is about 5% of contents and you say it’s too much...