For Example: T8 V [526~°C/84~G] (never set, its generated). Its nearest circulating object is about 1.7m Km away (Selena) and at 2304~°C! It's surface is completely molten und glowing noticably brighter)
This is due to the bug with brown dwarf luminosity.
Example 2 is the binary planet system around the orange dwarf. Both objects use similiar values as for parameters go (only light differences), but one of them is around 200~°C hotter. Other one still temperate as before. Shouldn't both of them be affected?
And this is a tidal effects. Try to change the moon's and planet's eccentricity to zero (their orbits around common barycenter).