Split word into Delimiter not functioning properly

What delimiter are you splitting on? It looks like you might be splitting on space " " rather than a line feed.

If you use the GUI to split your text column, it will produce a step that looks like this:

= Table.ExpandListColumn(
      Table.TransformColumns(
          Source,
          {{"Column1", Splitter.SplitTextByDelimiter(" ", QuoteStyle.Csv),
            let
                itemType = (type nullable text) meta [Serialized.Text = true]
            in
                type {itemType}
          }}), "Column1")

You can ignore most of that. Just focus on the Splitter part. Replace this

Splitter.SplitTextByDelimiter(" ", QuoteStyle.Csv)

with this

Splitter.SplitTextByAnyDelimiter({" ", "#(lf)"}, QuoteStyle.Csv)

if you want to split on spaces and line feeds.

Here's a full sample M query you can paste into the Advanced Editor:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCkktLjHVi8mLyUNnKcXqRCu55pWkFikU5+emKhRlJmcolKRWlChkpBalQqTT8ov0kABIc0lmbqpSbCwA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t]),
    #"Split Column by Delimiter" = Table.ExpandListColumn(Table.TransformColumns(Source, {{"Column1", Splitter.SplitTextByAnyDelimiter({" ", "#(lf)"}, QuoteStyle.Csv), let itemType = (type nullable text) meta [Serialized.Text = true] in type {itemType}}}), "Column1")
in
    #"Split Column by Delimiter"