[SOLVED] I can't seem to spawn influence anymore!

I fought both the Searing Exarch and the Eater of Worlds once. Now I need to run tier 14+ maps, and kill the influenced monsters to gain progress towards the next fight. I somehow have 5/28 maps progress towards the Searing Exarch, and 0/28 towards Eater of Worlds. But for the life of me I cannot spawn influence anymore. I'm running tier 16 maps, always killing the boss. Obviously I double checked to see if the particular influence is applied on the map device.

My friends tell me they're spawning influence on every map they're running (having also killed each boss once). I have no idea what I'm doing wrong.
Any suggestions would be very much appreciated.

[SOLVED] Another influence was applied (in my case, it was Elder influence applied by scarabs). So now we know why the elder scarabs are, and will remain, so very cheap.