opinions please

[Eramyl]

His dam was a spider pied and his father was a regular pied, so I know for sure that my spider is 100% het pied but there is no visually way to tell that.

Someone either lied to you, or you're presenting wrong information. There would have been nothing but spider pieds and regular pieds from that clutch. There's no way a het would have come from breeding two visual pieds.