I just sent the refund :-) You wouldn't know it, but behind the scenes that was quite a bit of work I knew I'd have to do at some point but I hadn't done yet. Glad it's done now.

{
  "expiration": "2022-04-12T14:35:15",
  "ref_block_num": 11315,
  "ref_block_prefix": 2463865480,
  "operations": [
    [
      "transfer",
      {
        "from": "v4vapp",
        "to": "erode",
        "amount": "5.000 HIVE",
        "memo": "Manual refund"
      }
    ]
  ],
  "extensions": [],
  "signatures": [
    "206a1e039a15fbfce888e15aaedfd8df41d6068e1d94742b876d3ab691b311934b02c4bdf9b004dfc8e88d8858a3c6f509470834e38c40d530fc1f910fdbe63a2e"
  ],
  "trx_id": "4fc9b40d198b95c5b9d03fd7ecc7be16810f9e61"
}