The text here is ambiguous. We cannot tell if Noah rebelled against his father Corihor or if Corihor joined Noah in his rebellion. The latter interpretation is possible since the Book of Mormon text allows a conjoined subject to be delayed, as in the following example:
This example from 1 Nephi has caused some difficulty (as explained under 1 Nephi 3:28). The correct reading is that Laman was angry with both Nephi and Lehi, especially since “and also with my father” is conjoined to the preceding “with me”. On the other hand, “and also was Lemuel” is conjoined to the subject noun Laman and means that Lemuel too was angry with Nephi and Lehi. (For further discussion of this construction, including a long list of examples, see the topic “delayed conjoined subject” under hebraisms in volume 3.)
The larger passage for Ether 7:15 suggests that Noah rebelled against both Shule and his father Corihor. Although earlier Corihor had been wicked, verse 13 explains that he repented:
Of course, Corihor could have joined his son Noah in the rebellion, but there is no further mention of Corihor in the narrative, which argues that Corihor remained loyal to Shule. The critical text will assume that Noah rebelled against his father Corihor as well as against king Shule.
The current punctuation, with commas around the phrase “and also his father Corihor”, does not resolve the ambiguity in any way. The critical text will remove these commas in order to facilitate the more probable interpretation. We should note that the last part of this verse also ends with two conjoined noun phrases that identify others who joined Noah’s brother Cohor in the rebellion. Once more there is an unnecessary comma after “Cohor his brother” that will be removed in the critical text. Thus the accidentals for the verse will read as follows:
Summary: Remove the confusing commas in Ether 7:15 so that the reader can more easily determine that Noah’s rebellion was against both Shule and Corihor.