I recently was asked if you could use the Add-Ins to delete records, particularly in the GL "Flex Budgeting" module. The answer, of course, is yes! The ability to delete records on forms was added to the Upload Wizard some time ago, and you can use it with just about any form to which you can map for adding and/or changing. And since you're just changing the way you interact with Lawson (in other words, you're using Excel as a "front-end" instead of LID or Portal), you're still making use of the Lawson application logic.
Read Deleting a GL Budget via Excel Add-Ins.