Judging from "The Carl Barks Library - Set VII", the first half of both versions of the page's scripts are basically the same.
In panel 3 of the alternate page the first nephew says "He seems to have passed away!" instead of the alternate "He seems to really be gone this time!" and the floating dead catfish shown in the original are removed. Apart from this, these halves look as alike as xeroxes.
Panel 4 also looks very much the same, though the alternate version doesn't show an added - but striked out - "to the dragon and the catfish?" in the nephew's question. The doctor's original answer in this panel is: "The rains, without a doubt!"
Unlike in the altered version, they continue in the next panel (5) by having the first doctor saying "Fresh water diluted the lake until it was only 98 percent impure!" and the second doctor adding "The dragon couldn't take it! He was poisoned!"
The last panel, which has the same text in the caption of both versions, the Junior Woodchuck leader is testing the water while saying "Scoriatic phosphates are bad today, troopers!" One of the three shown nephews, who are preparing themselves to dive, says "Coat yourselves with graphite and wear gas masks!" As conclusion, one already jumping nephew calls "Last one in is a pink balloon!" (as in the first page of the story). In the altered version, the happy nephews are swimming in a clean Lake Eerie, while saying that they hope "someone can figure a way to keep it this way!"

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