Exegesis:

apēggeilan de autois hoi idontes ‘and those who had seen (it) told them.’ Because hoi idontes has no object it is sometimes rendered as a substantive (cf. “the spectators”, New English Bible, “eyewitnesses”, Translator’s New Testament).

pōs esōthē ho daimonistheis ‘how the man who had been possessed was cured,’ syntactically dependent upon apēggeilan. For sōzō cf. on 7.50.

daimonizomai ‘to be possessed by a demon.’

Translation:

The sentence structure may have to be changed, e.g. ‘those who had seen how he … was healed, told them this,’ or, ‘those who had seen the healing of the man…, told them, how Jesus had done so.’

Them may have to be specified, e.g. ‘those who came,’ “the others” (Phillips); for the same reason Javanese shifts to a passive form enabling the continuation of the subject of v. 35, ‘they were informed by those who had seen.’

How he who … was healed, or, ‘the way Jesus had healed the man who…’ (Balinese), ‘how he … became well’ (cf. Marathi).

He who had been possessed, rendering the Greek aorist participle by a relative verbal clause in the past tense; most versions investigated, however, use (one of) their normal term(s) for ‘the demoniac,’ not making explicit the past tense. Where this is stylistically preferable it usually is acceptable, since v. 35 precludes the possibility of misunderstanding.

Healed. The Greek verb used here is in other contexts rendered by ‘to save’ (for which see on 1.47), but in most languages idiom does not allow to preserve this formal identity.

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.