Although the Marshalls take steps to keep their clothes dry when they swim to the underground caves, the Marshalls themselves are completely dry right after emerging from the water, including their hair. In multiple scenes, Holly's braids are perfect even though she has just swum. Similarly, even though their clothes are dry in the plastic bag, the clothes should become wet after the Marshalls put them on; they didn't towel off before dressing.
The Sleestak dormant season had ended four episodes earlier, but now they're in the midst of another one in this episode.
Enik establishes that the Marshalls haven't entered the Land of the Lost properly, which has fouled up the workings of the time doorway system, preventing him from returning to his own time. The time doorway is currently open to the moment the trio had disappeared from Earth, so the Marshalls must enter the mist that will return them to the Colorado River the moment their raft had went over the falls, which will allow the three Marshalls currently in the raft to arrive into this land properly, restoring order and allowing Enik to return home. However, Beauregard Jackson on the previous episode seemed to have gone back successfully on his own, without having to swap places with anyone.
The Sleestak that follows Holly into the water is able to emerge in daylight in the watering hole even though it has been established that Sleestak are terrified of and unable to function in bright light. Shouldn't the sunlight prevent the Sleestak from seeing Holly, let alone trying to follow her out of the water?