Equal and opposite deduction

This is what I always thought, but yesterday I saw the Hebrew text Rosh Hashanah (Ld.) learning Rosh Hashanah from Yuval from the words "in the seventh month" that appear both regarding Rosh Hashanah in Numbers (29:1) and in Yuval in Leviticus (25:9), and the Hebrew text says that this is an inference (and not a direct derivation) even though the verses are not related at all.

As in modern Hebrew, so also among the Sages, the word “hiksh” is sometimes used to express a comparison and not necessarily the degree of hiksh. The Torah links Rosh Hashanah to Jubilee by gaz”sh.

This also cannot be. Because the Gemara itself (at the end of the first third of page 34) brings a baraita that after bringing this inference it brings another equivalent derivation, and then the Gemara asks why the equivalent derivation is needed, since we already have the inference. So we see that here the inference is precisely what is meant.

Indeed, but the first one is really not a gaz”sh. The words in the seventh month that were said about the Jubilee are unnecessary, and they come to knock them down (from the exemption). This is not a seventh-seventh gaz”sh, which is what is presented below.