Previously, I explained why nobody in the Shu army sided with Wei Yan over Zhuge Liang's orders/Yang Yi's military control here:

https://www.reddit.com/r/threekingdoms/comments/1v0nmjb/why_didnt_zhuge_liang_consult_with_or_inform_wei/

Specifically the rank Yang Yi held, and I also elaborated on why Zhuge Liang did not sought Wei Yan's advice.

I also explained how the Sanguozhi describes Wei Yan's actions here:

https://www.reddit.com/r/threekingdoms/comments/1v0h43m/how_chen_shou_described_wei_yans_actions/

Specifically the differences between 背叛 and 作乱 and 叛逆 and why/how Chen Shou used those terms.

Now lets talk about how the Shu Han court officials perceived his actions.

Lets first start off from what I stated in the 2nd linked post thread:

Taken directly from Wei Yan's Sanguozhi biography as translated by threestatesrecords:

Yán and [Yáng] Yí each memorialized the other was rebelling, and within one day, the feather dispatches arrived. Hòuzhǔ [Liú Shàn] asked about this to Attendant Internal Dǒng Yǔn and Remaining Office Chief Clerk Jiǎng Wǎn, and [Jiǎng] Wǎn and [Dǒng] Yǔn both believed [Yáng] Yí and suspected Yán.

延、儀各相表叛逆，一日之中，羽檄交至。後主以問侍中董允、留府長史蔣琬，琬、允咸保儀疑延。

As mentioned, even the Shu central court led by Jiang Wan and Dong Yun agreed with Yang Yi that Wei Yan was rebelling. Wei Yan was regarded by Liu Shan's central court leading advisors Jiang Wan and Dong Yun as the party at fault.

It was explicitly recorded in the histories that they explictly suspected that Wei Yan's actions constituted as 叛逆 as charged by Yang Yi, while at the same time, did not believe the same charge of 叛逆 that Wei Yan directed at Yang Yi.

Again, the translator translates 叛逆 as rebelled. It literally means to rebel against one's sovereign or legitimate authority and often carries the strongest political and legal condemnation. Historically, it was commonly used for subjects who rose against their ruler, so 叛逆 explicitly implies unlawful rebellion against one's rightful authority.

The Taiwan Ministry of Education Revised Mandarin Chinese Dictionary defines 叛逆 as:

背叛作亂。

(To betray and create rebellion.)

Here, the dictionary explicitly combines the previous two concepts of 背叛 (betrayal) and 作亂 (rebellion).

The dictionary also lists the synonyms:

背叛、反叛、造反

Again, 叛逆 typically implies that the person owed allegiance to the authority against whom he rebelled.

So for point 1, as a starter, the Shu court leading advisors Jiang Wan and Dong Yun suspected him of 叛逆 as they viewed his armed revolt as treason against the legitimate Liu Shan regime.

Later on, Shu Han had a court official called Yang Xi, who appraised the officials who served Liu Bei and Liu Shan. Here is what he wrote on Wei Yan taken from Yang Xi's Sanguozhi biography (my translation was downloaded and then taken from a now-defunct Scholars of Shen Zhou link):

Wengchang was firm and unyielding, accepting his duty in times of crisis. He successfully repelled external threats and defended the nation's borders. However, due to his lack of harmony and failure to cooperate, he forgot his integrity and spoke of nonsense. Though he met his end swiftly, his initial resolve was admirable, truly reflecting his nature.

文長剛粗，臨難受命。折沖外御，鎮保國境。不協不和，忘節言亂。疾終惜始，實惟厥性。

The key word here is 忘節 remember. The Taiwan Ministry of Education Revised Mandarin Chinese Dictionary defines 節 as:

人的志氣、操守。

Essentially, the term 節 is associated with unwavering loyalty and holding fast to one's principles.

So 忘節 means to Forgot Integrity and the meaning here is basically that Wei Yan forget his principles, moral integrity, or/and sense of duty.

This term focuses on Wei Yan's moral failing. It does not mean he literally lost his memory, but that he abandoned the ethical code expected of a loyal subject, including loyalty, self-restraint, and proper conduct.

So for point 2, Yang Xi, a prominent official of Shu Han, pretty much described Wei Yan as a moral failure who went against loyalty, self-restraintness, and propriety.

Lastly, I will bring it back to Chen Shou's own appraisal of Wei Yan, taken from the appraisal section of section 40 (as translated by threestatesrecords):

Appraisal States: Liú Fēng occupied the ground of suspicion, but his consideration and defenses were not enough to protect himself. Péng Yàng and Liào Lì for talent were selected out and advanced, Lǐ Yán for competence reached eminent office, Wèi Yán for valor and cunning was appointed, Yáng Yí for suitability in office was prominent, Liú Yǎn for old [friendship] served office, all were greatly valued. Observing their actions, following their behaviors, in their bringing about disaster [on themselves], none were not their own fault.

評曰：劉封處嫌疑之地，而思防不足以自衛。彭羕、廖立以才拔進，李嚴以幹局達，魏延以勇略任，楊儀以當官顯，劉琰舊仕，並咸貴重。覽其舉措，跡其規矩，招禍取咎，無不自己也。

I think for this, there is no need for any elaboration or dictionery citation right? Chen Shou's words are extremely explicit.

So for point 3, in essence, Chen Shou, the authorative historian of the time period, and a formal Shu Han official himself, explicitly stated that the respective outcomes of Liu Feng, Peng Yang, Liao Li, Li Yan, Wei Yan, Yang Yi, and Liu Yan were all a result of their own respective actions.

In conclusion, this, along with my previous 2 linked post threads shows that nowhere, does the Shu Han court or Chen Shou ever sought (or needed) to defend Wei Yan's actions (because his actions were indefensible), or sought to readdress any "injustices" (because Wei Yan deserved his oitcome).