Preserve distinct peptone materials instead of an unsupported shared structural identity

The recovered #286 current-use diagnostic found 26 saved MediaDive occurrences
on PubChem:167312541: 25 Soy peptone occurrences (compound 75) and one
Vitamin-free casamino acids occurrence (compound 654,
mediadive.solution:1410#recipe/2, 1 g, source g_l=1). The legacy strict and
hydrate tables each assert both mappings. Their raw occurrences remain intact,
but a shared chemical node collapses distinct source materials.

Evidence and limited conclusion

The PubChem record really
does include soybean-peptone registry annotations and casein-digest synonyms;
its preferred glyceride title alone does not establish a mapping defect.
However, the same record supplies a fixed multicomponent structure and formula
C290H252N8O72. Those annotations do not demonstrate that either variable digest
is exactly that structure. PubChem's glossary
distinguishes structurally unique compound records from deposited substances.

The manufacturer's vitamin-assay casamino acids
is an acid hydrolysate of casein; its Bacto Soytone
is an enzymatic soybean digest. Two saved soy occurrences explicitly name
Bacto/BD Soytone; those qualifiers must not be transferred to the other 23.
These primary sources support material distinctions, not an exact supplier,
replacement registry identifier or newly inferred chemical composition for
every saved occurrence.

Independent scientific assessment and coordinator review agree that these two
finite name-to-target identities lack adequate structural identity evidence.
Preserve source observations locally and keep imported claims auditable; do
not globally ban this CID, all peptones or their database annotations.

Bounded implementation and acceptance

1. Add finite name/target identity holds for only Soy peptone and
   Vitamin-free casamino acids against this CID, covering existing unified,
   legacy, embedded and solution-name routes. Do not invent a replacement CAS.
2. Extend the existing material-scope audit with complete original mapping and
   source rows, locators, quantities and policy evidence. Distinct source-local
   materials must survive without inferred constituent/utilization edges.
3. Keep direct CID references, unrelated labels and supported MIM/pin bytes
   unchanged. Test both PubChem namespace spellings, fallback routes, negative
   controls, raw observation multiplicity and source finalization/admission.
4. Review any derived candidate metadata change separately, then replay and
   compare the actual source. All-source rebuild and candidate merge remain
   separate acceptance gates.

Evidence under data/issue1224-quarantine-20260929.xjuS9H/:

• issue286-display-join-mo25m5zm/groups.json, SHA-256
  56d0c510b84106de7a124f927f4428bab95a3879593bdca970424093e7092ec4.
• issue1241-review/peptone-167312541-independent-review.md, SHA-256
  641ec08af6c9e458d8173e7e25a5e216538fc0e0dae311637707c6420388ad01.
• Original strict/hydrate SHA-256 values:
  7e100314f1a62f675154aef7537be5b72ed2db9fbb8e8b1785198103aff31c71
  and d2bc349ae31990cf54ef308a14826c756be0e0ee874d35a0a6068d75ef04b3a3.

This is a scoped withheld identity, not proof of every historical CAS label,
new chemical-equivalence approval, a completed replay, or release acceptance.