Could someone point me to or explain the relationship between highest share found on a miner and the found block?
Current Difficulty is 336,899,932,796. So when your miner's best share meets or exceeds this number then it will have found a block, provided that the mining software in your miner is calculating it correctly.
Which the majority of miners don't do correctly, since the majority of miners are made by Bitmain, and Bitmain ignore our fixes to their hack fork of cgminer.