Maybe I'm confused, but it looks to me as if you're trying to split a string where there's one or more whitespaces.

Your manually-inserted example has a space, though it's hard to see.

It's 47.56.1.1[space]47.57.2.2 right?

I don't know what $RemoteSystem{'NetBios'}{$nic_service}{NameServerlist} puts into $test, but I don't see any spaces there.
--

($_='jjjuuusssttt annootthhrer
     pppeeerrrlll haaaccckkeer')=~y/a-z//s;print;
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