Where does “bluefin” come from?

I notice there's an issue with this etymological chain: it appears to conflate multiple unrelated words (blue, five in Yiddish, Latin finis, and various PIE roots) without a coherent pathway to "bluefin." A legitimate etymology for "bluefin" would be: blue (from Proto-Germanic *blewwaną, from Proto-Indo-European *bʰlew-) + fin (from Old English finn, from Proto-Germanic *finnuz). These are two separate etymological chains combined as a compound. Could you clarify or correct the chain provided? As written, it doesn't form a valid etymological path for "bluefin."

bluefin (English): bluefin tuna, any of a number of types of tuna...

Definitions

  1. bluefin tuna, any of a number of types of tuna...

Ancestry of “bluefin”, step by step

bluefin traces back through two separate lines of ancestry.

via English Blue

StepLanguageWordMeaning
1EnglishBlueA letterman at Oxford or Cambridge; A member of...
2Middle Englishblēwe
3Anglo-Normanblewblue
4Middle Frenchbleublue
5Old Frenchblöeblue
6Latvianblāvusaccusative plural masculine form of blāvs
7Old High Germanblāoblue, dark, grey; blue; yellow
8Proto-West Germanicblāublue
9Proto-Germanicblēwazblue; a dark bluish or grey colour, black
10Proto-Indo-Europeanbʰlēw-yellow, blond, grey

via English fin

StepLanguageWordMeaning
1EnglishfinOne of the appendages of a fish, used to propel...
2EnglishfinasterideA medication used to treat male pattern baldness and benign prostatic hyperplasia in males
3English-sterideUsed to form names of [[w:5α-reductase
4English-ideAny of a group of related compounds - azide,...
5Middle French-ideid (dynast)
6Latin-issuffixed to the root of nouns in composition,...
7Latin-asuffixed to the roots of verbs, forms agent...
8Proto-ItalicForms masculine agent nouns from prefixed or compounded bases
9Proto-Indo-European-éh₂
Every word from Proto-Indo-European bʰlēw-