I don't need no stinkin pics to have an opinion on amber trichs, and your low temp report supports my cartoon of trich development.
I suspect that trich ambering is the result of oxidation. Lower temps would delay oxidation reaction rate.
I believe trich ambering is like so many other guides, it's just a thing that people CAN observe, so it turns into a rule.
I rarely see any ambers in my grow, and I let a White Fire go 13 weeks just to see if it would amber. Nothing. Now I chop by clock at nine weeks and love it.
Your report may be the beginning of the end for a 'wives tale'.