丙 and 两 have a close relationship between each other. The paper below discusses etymology and diachronic changes of 丙 and 两. Therefore, ⿰魚两 appearing in Evidence 1 韻經五卷, after 蛃, is reasonable. I don't think we can immediately say ⿰魚两 is an error here.
IRG Working Set 2021v3.0
Source: LI Yuan
Date: Generated on 2025-02-12
Attributes
Evidence
““丙”与“两”二字形音义关系密切，使用时代互补，皆可证金文“两”为“丙”的分化字，
其量词用法继承自量词“丙””（p.36）
李建平、龙仕平2018 量词“丙”“两”的语源及其历时演变《古汉语研究》2018年03期,pp.32-38.
https://www.cnki.com.cn/article/cjfdtotal-ghyy201803004.htm
《韻經》五卷，成書于嘉靖十七年(1538)，張之象編輯。全書正文包含了古韻和今韻兩部分内容，其古韻參照吳械的《韻補》和楊慎的《轉注古音略》，繼承中又有自己的創見，今韻依據詩韻，并結合實際語音，分韻為一百一十六部。
https://cdmd.cnki.com.cn/Article/CDMD-10394-1015720357.htm
⿰鼠戾 is intermingled in Evidence1.
Data for Unihan