diff --git a/graphify/cache.py b/graphify/cache.py
index cc3a5a48b..63afc98ee 100644
--- a/graphify/cache.py
+++ b/graphify/cache.py
@@ -1592,6 +1592,24 @@ def save_semantic_cache(
     for fpath, result in by_file.items():
         cache_path, p = _recover_group_path(fpath)
         if p.is_file():
+            if cache_path != source_path(fpath):
+                # #2973: recovery only redirected the WRITE KEY. Each item in
+                # this group still carries the original unresolvable
+                # source_file string, and _semantic_entry_matches_path
+                # rejects an entry on read if any item's source_file doesn't
+                # match the path it was loaded under -- so leaving the old
+                # value in place would write a "successful" entry that can
+                # never actually be read back, silently reproducing the same
+                # loss this recovery exists to fix.
+                corrected = _normalize_value(str(cache_path))
+                result = {
+                    **result,
+                    "nodes": [{**n, "source_file": corrected} for n in result["nodes"]],
+                    "edges": [{**e, "source_file": corrected} for e in result["edges"]],
+                    "hyperedges": [
+                        {**h, "source_file": corrected} for h in result["hyperedges"]
+                    ],
+                }
             if allowed_paths is not None and cache_path not in allowed_paths:
                 warnings.warn(
                     "semantic cache skipped out-of-scope source_file "
diff --git a/tests/test_semantic_cache_basename_recovery.py b/tests/test_semantic_cache_basename_recovery.py
new file mode 100644
index 000000000..8aa204415
--- /dev/null
+++ b/tests/test_semantic_cache_basename_recovery.py
@@ -0,0 +1,30 @@
+"""#2973 — save_semantic_cache must recover a group whose reported
+source_file never resolves to a real file, by an unambiguous basename match
+against the already dispatched allowlist, instead of silently dropping it.
+
+A weak or local backend's adaptive-retry split path (llm.py bisecting a
+chunk that overflowed context and retrying) sometimes re-prompts with a
+reduced file subset and loses track of which of the original chunk's files
+a given node came from, so its source_file drifts to something that never
+resolves at all. Without recovery this silently discarded the group's nodes
+and edges from the cache on every incremental run.
+"""
+from __future__ import annotations
+
+import pytest
+
+from graphify.cache import load_cached, save_semantic_cache
+
+
+def test_malformed_but_basename_unique_path_recovers(tmp_path):
+    real = tmp_path / "sub" / "weird_named_file.py"
+    real.parent.mkdir(parents=True)
+    real.write_text("def f(): pass\n")
+
+    nodes = [{"id": "n1", "label": "f", "source_file": "lost_dir/weird_named_file.py"}]
+    saved = save_semantic_cache(nodes, [], root=tmp_path, allowed_source_files=[real])
+    assert saved == 1
+
+    cached = load_cached(real, root=tmp_path, kind="semantic")
+    assert cached is not None
+    assert {n["id"] for n in cached["nodes"]} == {"n1"}