HunyuanImage-3 (expert-parallel MoE) accuracy fails deterministically on
dev/vllm-align (SSIM 0.9490 vs 0.97, PSNR 26.21 vs 30 dB) while passing on
main's nightly. The align branch changes no hunyuan code; the drift comes
from the newer upstream vLLM (65a7b4628409, 585 commits past the v0.24.0
tag main tracks) shifting MoE kernel numerics. The image still renders
correctly and the mean/p99 pixel-diff checks pass — only the structural
metrics dip below a strict bar.
Per owner decision, re-baseline to the new stack: relax SSIM 0.97->0.94
and PSNR 30.0->25.0 (below the deterministic 0.9490 / 26.21, with margin).
The HunyuanImage CI job uploads no image artifact, so the reference PNG
cannot be auto-regenerated here; relaxing thresholds is the equivalent
re-baseline. main keeps the stricter bar.
Co-Authored-By: Claude <noreply@anthropic.com>
