I could be wrong but I thought miners were always in sync, miners are effectively writers to the ledger and single threaded. They all mine the same transactions in the same order. The first to find the hash with correct difficulty gets the block, which triggers the other miners to stop and verify. Once verified the new block becomes the seed for the next block. So the first transaction will always be processed before the second transaction. The second transaction would be committed as long as you had enough balance remaining after the first transaction.
Not true. Each miner may choose by whatever logic which transactions to include in the block they are mining. They are however are likely to prefer those which pay higher fee.
