TLIN1028-Q1: TLIN10285DDARQ1 Is the thermal PAD connected to any other pin internally？

See footnotes (2) and (3) of table 6-1, and notes 3 and 4 of the DRB package drawing in the datasheet. Also see [FAQ] Where do I connect the thermal pad of the logic QFN devices?

(The thermal pad is connected to the substrate, which is p-type silicon, which forms parasitic diodes with other components on the die, so its voltage must never be above GND.)