Although Situ Heng, Qin Song and Long Jiu were on the same mission, but because of Situ Heng's personality, they weren't very close. After Qin Song and Long Jiu reached an agreement, Situ Heng was livid and stayed that way for a long time. When Qin Song and Long Jiu taught Jun Wu Xie, Situ Heng scoffed at their efforts and did not show any interest nor did he help.
This time when the Spirit Lord had proposed for the three of them to help, Qin Song and Long Jiu were more than happy to, however as for Situ Heng.... Even the two of them were not confident that he would agree.
Situ Heng's character was gloomy and stubborn, he would not change anything once he has made up his mind. In his eyes, be it Jun Wu Yao on Jun Wu Xie, they were the thieves that had stolen the Spirit Tree's seed. If not for Qin Song and Long Jiu, he would have long targeted Jun Wu Xie's weakness that year and struck out against her!