G.R. No. 236050 - Domingo vs. Civil Service Commission

Petitioner Estrella M. Domingo is the Chief Archivist of the Archives Preservation Division of the National Archives of the Philippines (NAP).
Respondents are the Civil Service Commission (CSC) and Executive Director Victorino Mapa Manalo of the NAP.

On February 24, 2014, Mayor Strike B. Revilla of Bacoor City requested the NAP to provide resource speakers for:

Respondent Manalo initially confirmed the availability of four resource persons, including petitioner, for the Basic Records Management Workshop only.
Josephine F. Austria, Chief of NAP Training and Information Division, prepared the draft conforme letter, draft Travel Order, schedule of events, and Document Endorsement Form.
Respondent Manalo wrote instructions to put all in-house trainings on hold until after April 1, 2014, and returned the documents for revision.
Austria did not return the revised documents, which remained in her custody, leaving Bacoor City’s request unresolved.

Petitioner applied for leave of absence on April 10, 2014, for April 28-29, 2014.
On April 22, 2014, Mayor Revilla invited petitioner personally to serve as resource speaker for the Basic Records Management Seminar on April 28-29, 2014 at Tagaytay City, expressly as a substitute to the earlier NAP request.
On April 23, 2014, Bacoor City requested NAP’s official seal for the seminar.
Petitioner, Austria, and Lara Marie R. Abejuela attended the seminar on April 28-29, 2014; petitioner acted as resource speaker using NAP handouts.

On May 19, 2014, respondent Manalo issued a show cause memo for conducting the unapproved seminar and unauthorized use of NAP handouts.
On August 20, 2014, petitioner and Austria were charged with serious dishonesty, grave misconduct, and conduct prejudicial to public service; Abejuela was charged with simple misconduct.
Austria retired effective July 1, 2014; Abejuela resigned on July 25, 2014.
By Decision dated November 14, 2014, the NAP found petitioner guilty and dismissed her from service with accessory penalties (cancellation of eligibility, forfeiture of benefits, perpetual disqualification).
Petitioner’s motion for reconsideration was denied on December 5, 2014.
The CSC affirmed the dismissal on April 23, 2015; motion for reconsideration denied June 30, 2015.
Petitioner appealed to the Court of Appeals (CA), which affirmed the dismissal on June 1, 2017; reconsideration denied November 23, 2017.

Petitioner admitted attending the seminar without office approval and apologized.
It was shown that Austria communicated with respondent Manalo, and petitioner was unaware of the status of initial request.
Petitioner instructed Abejuela not to inform NAP about the April 28-29 seminar.
The City of Bacoor officially thanked NAP for participation after the seminar.

Is petitioner liable for grave misconduct, serious dishonesty, and conduct prejudicial to the best interest of the service based on: