If what the author is stipulating is true, wouldn't banks have just written themselves a check during the 2008/9 crisis and never involved the President or Congress? Basically a bank could avoid all crises by having enough global customers to offset risk they insert into each market. Yet, even global banks suffered during this crisis.
Compare with a loan. When loaning, the bank has a liability (balance in the receiver's account). That's the created money. It's balanced by the promise of payment later, plus interest.
It's not really that different to suggest that to buy a coffee machine, they're creating money as a liability (money in the coffee company's account) backed by the value of the coffee machine as a an asset.
So yes, something does change on the sheets[1] - JP now has another liability, and another asset. The limiting factor is that banks are required to have more assets than liabilities (capital) by proportion, because capital is what really gets used to pay for things like account withdrawals. The proportion JP actually has reduces as each purchase is made, which is why JP can't hold an unlimited number of coffee machines/buildings.[2]
[1] The article does actually mention this, buried in a sentence about a full analysis of JP's balance sheets.
[2] Without that requirement, if the accounts were all at JP, it could buy as many coffee machines/buildings as it wanted, but would collapse if/when the money created was withdrawn. Also see 2008.