▲ 蠕範（清光緒湖北叢書本）卷5 folio 8b

Evidence 1 (通雅) and evidence 4 (淵鑑類函) are direct quotes from 本草綱目. The text from evidence 2 (閩產錄異) is similar to 本草綱目. All of them were published at least 100 years later than 本草綱目 (1593).

Here we show how 鶾 transitioned to ⿱幹鳥.

The earliest known version, published in 1593, give a mixture of 鶾(green), ⿰龺⿱𫢉鳥(red) and ⿰龺⿱亼鳥(blue)


▲ 本草綱目（萬曆金陵本）卷48 folio 19b. (another version)

The 張鼎思 version, published in 1603, unified most shapes to ⿰龺⿱𫢉鳥:


▲ 本草綱目（萬曆張鼎思刊本）卷48 folio 30a

The shape ⿰龺⿱𫢉鳥 was then normalized to ⿱幹鳥: Here we can see ⿱幹鳥 in the 張朝璘 version, published in 1658:


▲ 本草綱目（順治張朝璘刊本）卷48 folio 30a

Here ⿱幹鳥 is a quote from 爾雅. 爾雅·釋鳥（四部叢刊本）gives 雗 (ctext), a semantic variant of 鶾:

I agree with Henry, the evidences are sufficient for encoding. The comment #13468 shows a small history of the glyph transition, it does not provide any unification suggestion.