Fix buffers in refit

[wdykas]

What does this PR do ?

Some persistent buffers were not being synced properly in refit. This is a fix for that.
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[wdykas]

/ok to test 9f8c74c

[wdykas]

/ok to test b0f324c

[wdykas]

/ok to test 677c0b8

[wdykas]

/ok to test c8cd5b2

[wdykas]

/ok to test f7572f5

[svcnvidia-nemo-ci]

🔄 Merge queue validation started!

You can track the progress here: https://github.com/NVIDIA/Megatron-LM/actions/runs/25380064991