Did I parse and interprete this sentence correctly?

Question

For full context: https://www3.nhk.or.jp/news/web_tokushu/2018_0202.html?utm_int=news_contents_news-closeup_002

The sentence in question: このほど、唯一残されていた、八王子隕石のかけらではないかとされる石について、本物かどうか、最新の科学技術で分析が試みられました。

My attempt at translation: "Lately, Concerning a stone treated as wether it is the only remaining fragment of hachioji meteorite, an analysis with latest technology was attempted."

Im especially skeptical wether I parsed the attributes correctly or not, although the translation seems correct at least.

Answer 1

このほど、
Recently,

〈唯一残されていた、｛（八王子隕石のかけらではないか）とされる石｝〉について、
(concerning/on) an only remaining stone which is considered (by some) as a candidate of a fragment of Hachioji meteorite,

本物かどうか、（最新の科学技術で）分析が試みられました。
an analysis was carried out using the latest technology to determine whether or not it's a genuine one.

The analysis was to determine 本物かどうか (whether it's a genuine meteorite fragment), not 唯一残されていたかどうか (whether it's the last one). 唯一残されていた simply modifies the following 石.

• XをYとする: regard X as Y; consider X as Y
• XをYではないかとする: regard X as a candidate of Y; consider X might be Y
• YではないかとされるX: X which is regarded as a candidate of Y; X which is regarded as Y by some people