Why? And what are your criteria for determining if the original words (and resulting translation) is too “vague”?
That type of question is similar to asking, “How big of a dirt pile is required before one calls it [in English, let alone in an ancient language in which extreme semantic precision is not always discernable because all of the native speakers are dead] a hill instead?” At how many feet high does a hill become a mountain —and does the presence of greenery versus bare rock impact that classification?
As to your question, if one lives in a relatively flat plain, for example, an elevation of just six feet is often called a hill. (I’ve personally observed that semantic phenomenon in areas of Texas and the Midwest. Also, some visitors from the Rocky Mountain states travel through the Appalachians and comment, “Heck. Those ain’t mountains. Those are just itty bitty hills!”)
Would “the high ground” qualify as a reasonable translation (instead of hill/mountain) of the ancient Hebrew text? I don’t know. With ancient languages sufficient corpus volume to reap sufficient concordance examples of word usage is not always available. After all, word meanings must typically be determined from comparing many contexts (plus contemporary and later translations, if available.)
How so?
I’m not familiar enough with his research and his geologic data (and meteorological data) to double-check his calculations. I only read the portion of the book available for free preview at Amazon, as well as some shorter articles he wrote on this topic in recent years. I’m not even a defender per se of his position. I’m simply citing it as one example of various hypotheses which are not in conflict with the Hebrew text of Genesis—and Morton’s may be one is known to some Peaceful Science readers.
I’ve observed floods of such a height. They struck me as extremely impressive floods. Moreover, they can certainly be catastrophically lethal. (Indeed, some of us remember the Bangledesh floods of 1966.) Moreover, the Noahic Flood was described as devastating not just in height/depth but duration. Over a year of such flood conditions is impressive indeed.
I vaguely recall him addressing that issue in the past but I have not read the relevant chapters of his recently published book. In any case, even under conditions of just a few days of devastating rains, leaving a water-logged area on foot can be virtually impossible. That happens even in some lowland floods in modern times—and I think Bangladesh has provided multiple examples.
It is not necessarily the role of the translator to “resolve” anything. (I may not understand your meaning here.) The goal is translation accuracy, clarity, and a sense of natural flow in the target language.
A flood of twenty-three feet reaching to the horizon in all directions is certainly tragic. I see nothing “pathetic” about it.
(@thoughtful Valerie may find this further-extended flood tangent of interest.)
One involves my kids, so it will be fun. 
The devil would also make such an argument. 