Dhrtarastra must have been very glad that Arjuna was not going to fight & was instead leaving the battlefield for the begging profession. But Sanjaya disappointed him again in relating that Arjuna was competent to kill his enemies. BG 1972 purports

Expressions researched:
"Dhṛtarāṣṭra must have been very glad to understand that Arjuna was not going to fight and was instead leaving the battlefield for the begging profession. But Sañjaya disappointed him again in relating that Arjuna was competent to kill his enemies"

Bhagavad-gita As it is

BG Chapters 1 - 6

Dhṛtarāṣṭra must have been very glad to understand that Arjuna was not going to fight and was instead leaving the battlefield for the begging profession. But Sañjaya disappointed him again in relating that Arjuna was competent to kill his enemies (parantapaḥ). Although Arjuna was for the time being overwhelmed with false grief due to family affection, he surrendered unto Kṛṣṇa, the supreme spiritual master, as a disciple.

BG 2.9 (1972), Translation and Purport

Sañjaya said: Having spoken thus, Arjuna, chastiser of enemies, told Kṛṣṇa, "Govinda, I shall not fight," and fell silent.

Dhṛtarāṣṭra must have been very glad to understand that Arjuna was not going to fight and was instead leaving the battlefield for the begging profession. But Sañjaya disappointed him again in relating that Arjuna was competent to kill his enemies (parantapaḥ). Although Arjuna was for the time being overwhelmed with false grief due to family affection, he surrendered unto Kṛṣṇa, the supreme spiritual master, as a disciple. This indicated that he would soon be free from the false lamentation resulting from family affection and would be enlightened with perfect knowledge of self-realization, or Kṛṣṇa consciousness, and would then surely fight. Thus Dhṛtarāṣṭra's joy would be frustrated, since Arjuna would be enlightened. by Kṛṣṇa and would fight to the end.