Issues with bone transform updates in UE 5.6 IK Retargeter (Pelvis Motion Op)

Development Character & Animation
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In the UE 5.6 IK Retargeter, I noticed that several bone transforms are not updating correctly within the Pelvis Motion operation stack.

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I identified the root cause in the FRetargetSkeleton::GetCachedEndOfBranchIndex() function.
When the Pelvis Motion operation runs (inside FIKRetargetPelvisMotionOp::Run()), it attempts to update the target pelvis and its children’s transforms using FRetargetSkeleton::SetGlobalTransformAndUpdateChildren().
To do this, the function retrieves the ChildBoneIndices array via FRetargetSkeleton::GetChildrenIndicesRecursive().

CachedEndOfBranchIndices[InBoneIndex] = INDEX_NONE;
const int32 StartParentIndex = GetParentIndex(InBoneIndex);
int32 BoneIndex = InBoneIndex + 1;
int32 ParentIndex = GetParentIndex(BoneIndex);

// if next child bone's parent is less than or equal to StartParentIndex,
// we are leaving the branch so no need to go further
int32 BoneIndexAtEndOfBranch = RETARGETSKELETON_INVALID_BRANCH_INDEX;
while (ParentIndex > StartParentIndex)
{
	BoneIndexAtEndOfBranch = BoneIndex;
	BoneIndex++;
	if (BoneIndex >= NumBones)
	{
		break;
	}
	ParentIndex = GetParentIndex(BoneIndex);
}

// set once (outside of while loop above) to avoid potential race condition
CachedEndOfBranchIndices[InBoneIndex] = BoneIndexAtEndOfBranch;

The problem lies here: Using data from the CachedEndOfBranchIndices array to create the ChildBoneIndices array causes an issue. If a child of a higher-level bone is interleaved among the child bones, the loop terminates prematurely. As a result, subsequent child bones located after that index are not added to the array, preventing them from being updated.

Is there any way to solve this issue other than creating a custom retarget operation?