Are these sentences correctly worded?

FYI-Gauros and Surthay are provinces of Thay. In the land of Thay in 1375 DR, Druxus Rhym, the zulkir of Transmutation, was assassinated in his home in Eltabbar, the capital city, by an unknown assailant. Meanwhile, without authorization from the council of zulkirs, Azhir Kren, the tharchion (governor) of Gauros, and Homen Odesseiron, the tharchion of Surthay, led their provinces’ forces in an invasion of the druidic realm of Rashemen, Thay’s neighbor to the north. However, the Rashemi somehow learned of the invasion and ambushed the Thayan army as it was crossing the River Gauros.