Irrevelant. Chase wrote:
If, therefore, it is true that the State of Texas was not at the time of filing this bill, or is not now, one of the United States, we have no jurisdiction of this suit, and it is our duty to dismiss it.
The secession of the state was not before the court.
"The first inquiries to which our attention was directed by counsel, arose upon the allegations of the answer of Chiles (1) that no sufficient authority is shown for the prosecution of the suit in the name and on the behalf of the State of Texas, and (2) that the State, having severed her relations with a majority of the States of the Union, and having by her ordinance of secession attempted to throw off her allegiance to the Constitution and government of the United States, has so far changed her status as to be disabled from prosecuting suits in the National courts.
The first of these allegations is disproved by the evidence...The other allegation presents a question of jurisdiction. It is not to be questioned that this court has original jurisdiction of suits by States against citizens of other States, or that the States entitled to invoke this jurisdiction must be States of the Union. But it is equally clear that no such jurisdiction has been conferred upon this court of suits by any other political communities than such States."
The question of secession was most certainly a question before the court, as you would have known had you read the decision. Had Texas seceded, the court would not have had jurisdiction. Had the acts of secession be illegal then the court would because Texas would still be a state.
BTW, who had seceded in the Penhallow decision?