I do not know the way to translate a string to a reference, may be it is possible through xs. But who guarantees that in every script invocation you have the same addresses in memory for your rows?

I suggest to use unique rowID instead of the reference to a row

Update:You can easily implement exactly what you want:

my %refhash = map {\$_ => \$_} @rows;

$dataref = param("hidden");
$date = $refhash{$dataref};
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But it's a bad way, don't do this.