» Which line does 'no wagering' actually remove?
Only the multiplier. In 30 seconds: the balance is still played once, usually at minimum odds of 1.50–2.00, only single bets count, and winnings are cut at the cap. Three lines remain and all three sit in the bet rules rather than on the campaign page.
Scenario: 100 units, odds 1.80, cap 200. One winning single: 180, all withdrawable. A 1.40 'safe' bet: refused, below minimum odds. An accumulator totalling 1.80: refused, singles only. Figures are examples.