At the time it was felt that engines and passengers could not survive the journey without a rest stop.
At the time it was felt that engines and passengers could not survive the journey without stopping a rest.
At the time it was felt that engines and passengers could not survive the journey without they stop for a rest.
1 is a random sentence I found on Internet, presumably on an British site; 2 and 3 are varied forms of 1.
Supposing 1 is good English, are 2 and 3 okay, too? If so, are there differences in meaning?