1) Two kill trackers for the same legend saying two different numbers. I remember it being on Horizon when she first came out, so my legend kills was suppose to match my season kills. However, the tracker was saying I was getting more kills during her season. (Note: This been fixed for awhile now)
2) I've had some damage trackers not properly count damage, mostly event ones. (Note: This also been fixed for awhile now)
3) There also was an issue where my overall account stats had said my highest kill count in a single match was 13 during S3. However, my highest was actually 17, (and still currently is). I just went to check this stat a few minutes ago, and I'm surprised to say that its now showing the correct number. This stat has been incorrect for several seasons now and I've last checked about 2 months ago, where it still had said 13. I'm not sure what had changed. (Maybe when we had lost our progress and it was added back, the tracker was properly updated).
Which @89413T are you looking at the tracker in-game after trapping enemy players? Sometimes trackers don't do live updates during matches, but they're still counting.
Also:
1) Is the tracker counting when you had trapped players in the ultimate and they didn't run out of the ring of fire?
2) Is the tracker also counting if they had ran out of the ring of fire? (It might not count players who run out of the ring of fire before the ultimate expires).
3) Were any players on the border of the ring of fire when the flames had landed, where they were running out of the ring of fire? (Flames have a delay between when the flames hit the ground and when they can start hurting players).
If they had ran out of the ring of fire during this time window, it might not had counted them as being captured as the ultimate was still being activated when they were running through the flames that had just landed on the ground.
Also, I went and used Google to translate your screenshot, should you need it in English. Although it says "Mother Road" instead of "Motherload", which I find to be a little bit funny.