Even though Tian Yu knew that he had arrived later than expected, he did not have a choice. The pill left behind by Junior Master Lin was simply way too strong.
As an inner sect genius, what sort of pill had Tian Yu not seen before? Just the smell of something would allow him to analyse what sort of pill it was. But yet, he could not figure out what Biggra was.
When Lin Fan arrived in Glory Sect, Tian Yu was not around as he was out in the forbidden grounds expedition.
Furthermore, upon his return to the sect, his cultivation foundation was destroyed. Hence, he was in a state of mental torment. As such, he knew nothing much about the affairs within the sect, let alone the fact that Nameless Peak had been given to someone else by the Grand Master.
Whether or not the pill was poisonous, he could not be bothered. He was just a disabled man. Would anyone still want to take advantage of that?