We are not sure of what his message was to the tower, it could well be canceling IFR at 1505 ft (above ground!) and announcing entering the circuit for 13 right-hand.
There is at least one report of quite reasonable weather at LOAV but this was an observation on the ground, so I m assuming horizontal visibility.
The point of impact is 1.5NM ( 90 seconds at 120 knots) exactly on an extended downwind for 13 with no information about impact height, but the maps show that area to be between 1400 and 1600 ft.
This means not only was point Tango missed (turn to base leg 1) but also a descent to point of impact at around 1500 ft. At 700 ft per min (engine failure) this would take over a minute(engine failure). However as far as we know, no mayday call was made.
I see the following options:
1. medical occurrence on non-autopilot downwind resulting in slow descent and inability to send mayday, such as stroke or heart attack
2. mechanical failure but this does not explain lack of Mayday call
3. intended non-autopilot low circuit due to weather in apparent limited but possibly intermittent visibility but with grey indescript (no contrast) clouds ahead and sudden (re)entry in IMC resulting in disorientation and CFIT
I think it would be logical to not be on autopilot if in a bad weather circuit, especially in the mountains as one would assume having faster control of the plane in case of "issues"
I do not rate the quote of the mountain man about the sound. The sound would have been peculiar because the plane was closer to his mountain than other planes in the circuit. More important is that he did not hear a rev UP (spool up) of the engines as a plane intending to initiate a fast climb, so medical issue or not, it sounds like CFIT to me.....
Today both the family of the pilot and his company (ELEKTA) each put their condolences adverts in the Telegraaf, Holland's most widespread newspaper, the 2 adverts taking up 1/3 of the page. Impressive. We sometimes forget how many lives are touched in these matters. In his case there were many, and intensely so.