Stories of the Japanese 01336 [Muromachi/Yoshimochi Period] Seppuku of Akamatsu Mochisada

Following Yoshimochi's order to subjugate Akamatsu Mitsusuke, branch families such as Akamatsu Mitsuhiro and Sadamura, as well as Yamana Tokihiro, began preparations for battle under the Shogun's command.
However, there were many who opposed Yoshimochi's order. On November 3, 1427 (the 34th year of Oei), the Kanrei, Hatakeyama Mitsuie, remonstrated against Yoshimochi's order, calling it "rash," and opposed the military expedition. Even the senior vassal Hosokawa Mochimoto (1399–1429) refused to move his troops despite receiving daily reminders from the Shogun. Even Mansai, who was usually obedient to Yoshimochi, criticized it as a "hasty judgment."
On November 4, Yamana Tokihiro departed for the subjugation, but Isshiki Yoshitsura did not depart, citing various excuses.
Now, the subjugation of Akamatsu Mitsusuke was resolved in an unexpected way. On November 10, when Yoshimochi was passing in front of the gate of the Sanjo-bomon residence after finishing a visit to Hatakeyama Mitsunori's mansion, a monk appeared offering a letter. In other words, it was a direct appeal.
When the attendant Hatakeyama Mochishige took this letter and showed it to Yoshimochi, it contained information about an illicit affair involving Akamatsu Mochisada, who had been granted Harima.
Enraged, Yoshimochi immediately had his close aides interrogate Mochisada. Mochisada pleaded his innocence, but Yoshimochi dismissed it, saying the "charges are clear." Mansai, who was begged by Mochisada for help, appealed to Yoshimochi on November 12, saying, "You should first verify the facts," but Yoshimochi replied,
"I have already questioned that maid (referring to the affair partner), and the situation has already been clarified,"
and would not listen. Mansai left without being convinced, met with Akamatsu Mochisada, and recommended,
"Why don't you retire to Mount Koya for a while and plead your innocence?"
Mochisada agreed to this.
The next day, Mansai went to the Sanjo-bomon residence again to plead for his life, but Yoshimochi refused, saying,
"I have already sworn to God that I would put him to death,"
and ordered Mochisada to commit seppuku.
In the end, Akamatsu Mochisada was forced to commit seppuku on November 13, and the subjugation of Mitsusuke was called off. Mansai wrote in his diary, "A miserable act of a heavenly demon," and lamented.
What does this downfall of Mochisada mean? Does it mean that Yoshimochi had a gullible personality where he would believe anything as soon as he received information?
Alternatively, it has been pointed out that Mochisada may have been used as a scapegoat to stop the subjugation of Mitsusuke. In other words, a rebellion plan by the Kanrei Hatakeyama and others was rising against Yoshimochi, who was forcing the subjugation of Mitsusuke, and upon learning of this, Yoshimochi had to fabricate some reason to cancel the subjugation of Mitsusuke.
In any case, it can be considered that Yoshimochi was either a capricious dictator or had a cruel personality that would discard even his close aides for the sake of self-preservation.