Chapter 12, lightning payment routing

[YazidKurdi]

"Now, Diana has secret R. Therefore, she can now claim the HTLC from Carol. Diana transmits R to Carol and adds the 1.001 bitcoin to her channel balance (see Step-by-step payment routing through a Lightning Network step 7). Now the channel balance between Carol and Diana is: 0.999 to Carol, 3.001 to Diana. Diana has "earned" 0.001 for participating in this payment route."

In the above paragraph, Diana has already paid Eric 1 bitcoin, leaving their balances:
Eric's balance: 3 bitcoin
Diana's balance: 1 bitcoin

When Diana transmits secret R with Carol to claim the BTC locked in the HTLC and add 1.001 bitcoin, shouldn't the channel balances be reflected as:
Diana's balance: 2.001 bitcoin --- rather than 3.001 bitcoin
Carol's balance: 0.999 bitcoin

Thank you