My guess is, from looking at Data::BISON::Base, as the error message says, that the following piece in the custom method creator is to blame:

...
            {
                local @ISA = @{ $caller . '::ISA' };
                $self->SUPER::__parse_args( $args );
            }
...
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Most likely because the author didn't bother to clean up @ISA properly.

But then, looking at the whole code, I wouldn't touch it because I don't understand why the author chose to do all method creation in a import subroutine instead of plainly declaring the methods outside and then using glob assignments to export them. Maybe you want to get in contact with the author to ask about the motivation and intent.