So you want to have '2222987' as key and 'TMW2222987' and '66' as values? In that case you could use a two-element array or just concatenate the two values into a string:

$ids{$accountnumber}= "$acc_id:$1$accountnumber";
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The $1 is what was matched with the first parenthesis in your regex, so should be 'TMW' or ' ' or '' or ...

You get both values separated again with:

my($acc_id,$fullaccount)= split /:/,$ids{$accountnumber};
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