At the time Judas & Peter etc did not know of Salvation c/- death, burial, resurrection of ChristYes, the OSAS believers used a wrong tactics here. Instead of painting Judas 'never believed', 'devil' in the first place, why not paint him as a true believer who repented for his sin and is forgiven by GRACE, by blood of Jesus. So, Judas savation never lost. He is with Jesus in heaven !!
There is no sin Jesus's blood cannot wash away, isn't it?
Matt 16:
21From that time forth began Jesus to shew unto his disciples, how that he must go unto Jerusalem, and suffer many things of the elders and chief priests and scribes, and be killed, and be raised again the third day.
22Then Peter took him, and began to rebuke him, saying, Be it far from thee, Lord: this shall not be unto thee.