Moving speed of raiders and animals is not affected by light levels. Colonists have 80% debuff for moving in darkness, which makes dealing with raids during nights a much more hard task.
I think for animals we can skip that debuff, but for raiders, yeah, it would make sense if they were affected. Though I can't think of any reason we'd disable this for them and it seems like something we must have done intentionally...
I haven't been able to reproduce this for raiders. Seems like it has already been fixed. Thanks for reporting! ;)