While I cannot find the initial post, I can find articles about the resurgence in discourse over this issue following the Oct. 7th attacks. The Anti-Defamation League labels continued accusations of Judaism for this claim are little more than conspiracy, or antisemitic rhetoric, playing off of a variety of Jewish stereotypes, mainly the "blood libel trope" which has existed for centuries(https://www.adl.org/resources/article/unfounded-claims-organ-harvesting-reignite-embers-decades-old-hospital-scandal). That ADL article also lists Swedish author Donald Bostrom as a key figure in re-igniting this fire, referencing an article he wrote (but later recanted) in 2009 claiming the IDF harvests the organ's of Palestinian's. He went on later to say he had no proof(https://www.haaretz.com/2009-11-02/ty-article/i-have-no-proof-the-idf-harvests-palestinians-organs/0000017f-df89-df9c-a17f-ff993e8a00000). The article also mentions the Israeli Hospital, and mainly a Dr. Yehuda Hiss, as committing widespread violations from the 90s into the 2000s, but that a state-led investigation into the event showed they were not targeting Palestiniens.
The claims in the post you saw likely came directly from/are referenced in this article, https://www.aa.com.tr/en/middle-east/gaza-authorities-accuse-israel-of-stealing-organs-from-released-palestinian-bodies/3719641, where they quote the director of the Palestinien government media office as saying “Parts of many corpses were missing, including eyes, corneas, and other organs,” Thawabta noted, which he said confirms that the Israeli army “stole human organs while holding the bodies,” calling the act a “barbaric crime.” (Majed, Sio; 2025) Mind you, the Anadolu Agency (AA) who published that article is a Turkish state-run media outlet known for spewing Turkish anti-Isreali propaganda.
While this does not prove or disprove the claim, it seems like the post you saw was referring to this article or the hateful language surrounding these issues to further a stereotype, or, that same stereotype influenced the words of that Palestinien official. In any case, I could find little to no evidence from not obviously biased or state-alligned media outlets to support this claim, yet the timing and circumstances coincides very well with the periods when Israel was returning hostages/bodies.