Since the foreign races' location was known, as well as the conditions under which they would emerge, even though the threat of the concealed army was very frightening, Su Mo had the Divulgence of Heaven's Secret talisman. As long as they were in the talisman's simulation world, the foreign races' army would have their disguise stripped away and exposed once he successfully arrived at the Great Canyon.
Hope One's maximum speed was 31 knots, which was around 60 kilometers per hour after conversion.
The Great Canyon was 120 kilometers north of the basin. Even if he did not use the special ability "Charge", he could still reach the location in around two hours.
If they did not have to take any detours when the ocean emerged and traveled in a straight line, three hours was sufficient to enter the canyon and even cross most of the distance.