p. 270
‘यस्त्वेतेभ्यः’ इत्यादिना उक्तमेवार्थं पुनरपि दर्शयति अवश्यकर्तव्यत्वप्रदर्शनार्थम्—
In plain words
The point he already made in the passage beginning "but one who, from these…" he now shows once more — to make plain that this has to be done—
Close to the Sanskrit
By the passage beginning 'yas tv etebhyaḥ', the very meaning already stated he shows once again, for the purpose of displaying that it must necessarily be done—