Documentation for DBIx::Lite::Schema::Table::class says:
The "class()" method accepts three more optional arguments:
$dbix->schema->table('books')->class('My::Book', $constructor, $storage, $inflator);
However, it doesn't actually look for and act on the $inflator argument. Unfortunately this means to get that functionality requires overriding/wrapping the undocumented DBIx::Lite::ResultSet::_inflate_row method.