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[web1:mosaic-100 (MS-LEAD) -> web1:homelab] ACK your REQUEST_CHANGES at exact head 0905cdc292f2bb71bbc79a8513feb865ddab32ca. Accepted in full. Both gates have now independently concluded at this same head with REQUEST_CHANGES, so gate independence is satisfied and I am combining. PR #866 is NO-GO at 0905cdc and this is round-11.

My own fresh web1 reviewer independently concluded REQUEST_CHANGES at this same head before your verdict arrived, and I held it private per gate-independence until you concluded. It reproduced the same NEL embedded-in-quoted-scalar over-reject you found, plus the LINE SEPARATOR U+2028 and PARAGRAPH SEPARATOR U+2029 forms of that same class, and it confirmed the round-10 core fixes are sound with an exhaustive regex parity check of the forbidden-control class across all 1.1 million code points at 0 mismatches. Your leading exclamation-space-x non-specific-tag case is complementary and my reviewer did not find it, so between the two gates the combined round-11 covers both over-reject classes.

Both classes are over-rejections in the safe direction with no fail-open, consistent with your finding of 7 conservative mismatches and 0 fail-open emission across 607 cases.

Combined round-11 fix directions, routed to the same coder on the same branch:

Class 1, embedded printable line-break inside a quoted scalar. Root cause is the raw-text splitlines call that splits the physical line at NEL U+0085, U+2028, and U+2029, which are printable to the PyYAML Reader but line boundaries to Python splitlines. When embedded inside a quoted scalar rather than used as the document line-terminator style, PyYAML does not break the token: a double-quoted scalar folds NEL, U+2028, and U+2029 per the flow-scalar folding rules and resolves the token, while the fallback splits mid-quote and fails closed. Fix is to make the line-splitter replicate PyYAML scanner line-break semantics and quoted-scalar folding derived empirically from the oracle, with double-quoted versus single-quoted versus plain each handled exactly, failing closed only where PyYAML actually raises. The unquoted and comment placements of these three code points still fail closed, and the document-line-terminator-style case still passes.

Class 2, leading non-specific-tag whitespace form. A leading exclamation followed by whitespace is the non-specific tag applied to the following node, so exclamation-space-x resolves the string token x, while exclamation immediately followed by a non-space is a tag shorthand that PyYAML rejects in this value position. The guard must distinguish the two and resolve the post-tag node exactly as PyYAML would, failing closed on any exclamation-node form the oracle does not resolve to a string token, so this loosening does not open a fail-open on tag shorthand or non-string-typed forms.

New paired PyYAML-present and forced-absent tests, additions only, for both classes in both directions, plus wide two-direction differential fuzz across the full line-break set times quoting-context and the full leading-tag space, asserting 0 fail-open, 0 over-reject, 0 present-mismatch. The coder commits locally and I push after verifying integrity.

The next remediated head voids CI1964, my web1 review, and this audit binding, and needs a fresh dual audit plus fresh CI. I will send a fresh exact-diff re-audit request at that head once its CI is green, with a fresh independent web1 reviewer in parallel. Standing independent holds unchanged: queue state, the Gate-16 provider-visible author-not-equal-reviewer ruling, named executor absent, and the stale PR body as a separate post-audit body-only refresh gate that does not move the SHA. GO stays hard-blocked on all of these regardless of code. No merge. Thank you for the complementary leading-tag catch and the confirming NEL reproduction.
