Can someone decipher this deadlock for me?
2 Types of deadlocks. 
    1. true cycle in the waits-for graph
    2. waits-for graph that is too expensive to check for cycles.

If InnoDB has to check more than a million locks in a graph, or if it recurses 
through more than 200 transactions while checking, it gives up and says there's a deadlock. These numbers are hardcoded constants and cannot be configured (although recompile is possible). 

The last line suggests Transaction 1 was chosen as a deadlock victim and was rolled back. 

Thus when you re-run the transaction that was rolled back, it might have to wait for other transactions to complete, but typically the deadlock does not recur. Please try...