You can do a search about this as it has been discussed in the past. However, another readily available source is the book - well worth reading if you have an interest in this topic - The Hole by Drew Wilson. He states that the guy under the toppled cabinet had a tattoo on his hand which would not have been Capt Andresson's. Wilson's source is the late former head of the JAIC, Andi Meister, quoting Lopetamatta logiraamat ['The Unfinished Logbook', Baltic News Services, 1997]. According to Jutta Rabe from p. 140, the two eyewitness sources were two Finnish armed forces guys who said that clearly visible in these videos was Capt. Andresson with a 'shot through the head'. Now, my view is that (a) Finns tend to tell it as it is (authenticity) so I do believe them if that is what they say they saw. (b) this doesn't necessarily signify murder. IMV it could well be suicide in the face of near certain death, as being the captain, he couldn't leave the ship, as Andresson was very old school and trained at a Russian naval academy. In WWII, torpedoed German ships would have a flurry of SS officers shooting dead their wives and children before killing themself, rather than face drowning and fear.
Note: words in italics indicates the title of a book.