Unable to earn "Kamikaze" and "Road Rage" achievements

[Synovus]

After earning 92 other objectives without any problems from RST I find myself unable to earn these 2 achievements despite proper means. Using version 0.10.3.3 with Windows 8 x64 on my main character, Synovus.

Road Rage was not awarded after 5 consecutive roadkills at the same timestamp though the Road Kill and kill combo achievements were awarded.

http://imgur.com/a/90Sfy

Road Rage screenshot from 7/23/15 session at 21:27:18
Kamikaze screenshot from 5/26/15 session at 17:58:33

I was unable to earn Kamikaze on my alt character either, though I have not tested Road Rage on my alt.
Had a friend test Road Rage yesterday and was able to earn it, though I have not had a friend test Kamikaze.