brahmaṇā coditā vayam
avatīrṇo ’si viśvātman
indram — as Indra; naḥ — our; tvā — to You; abhiṣekṣyāmaḥ — we shall perform the bathing ceremony of coronation; brahmaṇā — by Lord Brahmā; coditāḥ — ordered; vayam — we; avatīrṇaḥ asi — You have descended; viśva-ātman — O Soul of the universe; bhūmeḥ — of the earth; bhāra — the burden; apanuttaye — in order to alleviate.
As ordered by Lord Brahmā, we shall perform Your bathing ceremony to coronate You as Indra. O Soul of the universe, You descend to this world to relieve the burden of the earth.
Surabhi makes it quite clear in this verse that she has had enough of the leadership of imperfect demigods like Purandara (Indra), and now she is determined to directly serve the Supreme Lord. Since Brahmā has ordered her, her attempt to coronate Lord Kṛṣṇa as her personal Lord is authorized by higher authority. Moreover, Lord Kṛṣṇa Himself comes down to the earth to relieve the burden of self-destructive, mundane administration, and thus it is perfectly consistent with the Lord’s own purpose that He become the Lord of Surabhi. Since the Lord rules millions of universes, He can certainly take care of mother Surabhi.
In fact, Surabhi wanted to bathe the Lord for her own purification, and she earnestly makes her proposal to Viśvātmā, the Soul of the universe, Śrī Kṛṣṇa.