I'll offer that the cold may affect the battery, wiring, and friction-fit metal connections/terminals.
Metal expands and contracts proportionately to it's temperature state(s), which may affect the contact points of wiring harnesses and connectors. Albeit perhaps a very fractional difference, this might be part of your issue.
Additionally, increasing heat within an electrical system incurs a corresponding increase in the electrical resistance of the system. Conversely, decreasing the temperature will decrease the resistance.
Perhaps your decrease in temperature allowed an otherwise failing battery to sustain the necessary amperage for start/boot-up, due to a decrease in system resistance…?
…could also be thermal sensor related, keeping extra cold will obviously prevent overheat-protection from being engaged. Decayed thermal paste is likely, and unless you have a verified functional spare battery available, this would be primetime to investigate the heatsink and any / all physical connections.
Good luck.