C. John Collins Discusses "in him all things hold together" (Colossians 1:17): See Link

https://www.bsw.org/biblica/vol-95-2014/colossians-1-17-hold-together-a-co-opted-term/549/article-p64.html

From my perspective, it's possible that "in him" could have the same meaning at Col. 1:16 and v. 17.