p. 256
दमोऽष्टादशदोषः स्यादिति ये दोषा उक्ताः, तान् दोषान् परिवर्जयेत् ।कस्मादित्याह—तेषु दोषेषु त्यक्तेषु प्रमादी न भवेदित्यर्थः ।सोऽपि अप्रमादः अष्टगुणो मतः; ‘सत्यं ध्यानम्’ इत्यादिना पूर्वमेवोद्दिष्टत्वादित्यर्थः ॥
In plain words
The faults named in the line "restraint has eighteen faults" — those are the ones to be let go of, and let go of completely. Why? The text answers: because once you have dropped them, you must not go slack. And that vigilance, apramāda, is itself reckoned to have eight parts — no need to list them again here, since they were already set out earlier in the passage beginning "truth, meditation." That is the sense.
Close to the Sanskrit
The faults which were stated by 'restraint would be that which has eighteen faults' — those faults one should thoroughly abandon. Why? — to this he says: when those faults have been abandoned, one should not become negligent; this is the meaning. That non-negligence too is held to have eight qualities; because it was already pointed out earlier by the passage beginning 'truth, meditation' — this is the meaning.