[Flaky CI] `forward_absorb_fused_mla_rope_prepare` not working

[Fridge003]

Checklist

• 1. I have searched related issues but cannot get the expected help.
• 2. The bug has not been fixed in the latest version.
• 3. Please note that if the bug-related issue you submitted lacks corresponding environment info and a minimal reproducible demo, it will be challenging for us to reproduce and resolve the issue, reducing the likelihood of receiving feedback.
• 4. If the issue you raised is not a bug but a question, please raise a discussion at https://github.com/sgl-project/sglang/discussions/new/choose Otherwise, it will be closed.
• 5. Please use English, otherwise it will be closed.

Describe the bug

Errors inside self.forward_absorb_fused_mla_rope_prepare, only happening on AMD tests.

https://github.com/sgl-project/sglang/actions/runs/18979106892/job/54206754545
https://github.com/sgl-project/sglang/actions/runs/18979106892/job/54206754553

Reproduction

N/A

Environment

N/A

[Fridge003]

Covered by #12574