@sechel83 In his letter, Rav Aharon Feldman makes a distinction between “Elokists” and “Meshichists”. He specifically refers to Meshichists as dangerous because they believe a dead man can be Moshiach. So there’s my one non-Chabad Rov thus fulfilling your request of “please bring one open statement from a non chabad rov that there’s something wrong with believing that a dead man can be Moshiach”
Nu? So I answered your query, have you answered mine? Have you found some random Rabbonim to talk to?