I have started to collect veterans for 3 months ago. I just reach 6* both of them just before the event release. The drop rate was not good but also not too bad. But when the event released this drop ...
I understand how you feel. I’ve been farming reaper since it was farmable and yet I 7* fosftf and still am working on reaper??!! It feels like that 33% is in a pie chart. And the chart is actually a wheel that rotates. You have a good streak for a while then you hit the 67% desert of pain in the ass nothing for a long time. Keep farming and you should find the oasis soon. Unfortunately it might be to late.