• kṛṣṇa kṛṣṇa — O Kṛṣṇa, Kṛṣṇa
  Vocative, doubled. Gauḍīyas treasure the repetition: the mahā-mantra itself doubles the names. The boys' frightened doubling is the form mahā-mantra takes when the throat cannot manage anything else.
• mahā-vīra — O most powerful one
  Compound: mahā (great) + vīra (hero). They call on His strength in the moment of weakness — the precise grammar of śaraṇāgati. One does not appeal to one's own vīrya; one appeals to His.
• amogha-vikrama — You whose prowess is never thwarted
  Compound: a- (not) + mogha (futile) + vikrama (prowess). Every Vaiṣṇava prayer rests on this conviction: Kṛṣṇa's saving action never fails. Without amogha-vikrama, prapatti would be a gamble.
• prapannān — who are surrendered
  Past participle of pra + √pad — the surrendered ones. The same word the Gītā uses at 18.66 (mām ekaṁ śaraṇaṁ vraja). The boys explicitly identify themselves under this title to claim its corresponding protection.
• trātum arhathaḥ — please save
  Infinitive of √trai (to protect) + arhathaḥ (You two ought to). The dual ending addresses both Kṛṣṇa and Balarāma. The grammar enacts what the boys know — protection in Vraja is given by both brothers.

The boys' cry — Kṛṣṇa! Kṛṣṇa! O Rāma! — is the rawest Vraja form of nāma-saṅkīrtana: repeated name, no philosophy, no theology, just the Beloved called twice. Caitanya tradition holds this as the highest emergency-mantra: when surrounded by the fire of saṁsāra, repeat the name and trust the prowess that has never failed.