The report spends a lot of time on the associated warnings from the original unsafe gear indication (horn and EGPWS) and is critcal that the crew ignored those warnings. Suggesting they should have gone around and sought further advice. What would that advice have been?
The report does not state if the horn or EGPWS receives indications from both gear indicating systems or just the primary. If it only receives it from the primary then the crew were correct in their assessment of what they expected to hear. If it gets it from both and the horn and EGPWS were an additional bit of important information then why weren't they in the QRH?
The whole point of OEM documents such as the AFM and QRH are so that you don't have to ring the OEM and ask for advice when it is time critical.
My aircraft type has multiple undercarriage indications but the OEM is very clear that only one of them has to indicate a green to be certain that it is down and locked. Nevertheless I would have a sense of unease during the approach, just like these guys did. So the fact they were uneasy should not be miscontrued to mean that they thought that needed more advice.