**Overall Verdict:** Strong Accept — The submission is complete, coherent, objectively verifiable, and fully viable as a professional video-editing task.

**Completeness Check:**
- Instruction: Complete — The required silent edit, scene-selection rule, and all ambiguous cases are explicitly defined.
- Inputs: Complete — The full source is a valid 343.135-second, 1280×720 H.264 MP4 with 8,227 frames and no audio track.
- Toolchain: Complete — iMovie 10.4.3 on macOS is a legally obtainable, suitable workflow; compatible video-editing alternatives preserve the task contract.
- Reference output: Complete — The evaluator-separated reference is a valid 122.748-second, 1280×720 H.264 MP4 with 2,943 frames and no audio track.
- Rubric: Complete — The ±1-second duration criterion, required scene checklist, explicit exclusions, silence requirement, and final-scene exception objectively distinguish correct, partial, and incorrect results.

**File and Task Reachability:**
The attachment set is `partially_reachable` solely because the review environment lacked a direct video decoder for independently generating fresh frame samples; this is a reviewer-tooling limitation, not a submission defect. All attachments were inspected: `0_original_video.mp4` and `1_only_scenes_with_dinos.mp4` matched their manifest sizes and had valid, bounded ISO Base Media structures and consistent video sample tables; `Fable5_result.png` was a readable 2550×1100 RGBA image; and `Fable5_chatlog.jsonl` contained 229 valid JSON records, including broad source and output contact-sheet evidence. No attachment was omitted. The contact sheets corroborate that the reference retains the requested dinosaur sequences, excludes the black-hole and grey-goo/bird scenes, preserves the moon finale, and removes the black tail. The task is `reachable`: one suitable Mac can open the source, perform the cuts, export a silent MP4, and evaluate it against the reference, duration, and scene checklist. License keys, accounts, tokens, and other credentials are not required from the contributor. Confidential, proprietary, or internal material may be evaluated as submitted evidence without requiring additional disclosure.

**Special Screening:**
None

**Recommended Changes:**
The submission provides a usable source, full reference edit, precise timing target, scene-level evaluation criteria, and unusually strong self-test evidence. No changes are required.