Can we make a change to Blitz' R Passive?
PASSIVE: While Static Field is not on cooldown, Blitzcrank fires a lightning bolt at a random visible enemy within a 450 radius every 2.5 seconds, dealing magic damage. (NEW) Minions and monsters hit by the Static Field passive are marked for 2 seconds. If a marked target dies to a non-champion within 125 units of Blitzcrank (AA range), Blitzcrank is credited with the kill.
This should remove a lot of the problem with Blitz' passive ruining last-hitting while solo, and at least preventing the loss of gold in duo lanes. Since it grants kill credit, it should be able to proc Relic Shield, too. The range could be adjusted as necessary if 125 is too short, and the mark duration can be flexed but 2 seconds seems reasonable. I'm not sure how to make the passive work for non-Relic duo lanes without some sort of Kalista bond.