No, not using the 'overkill' command as it relies on the editor for selection.
You could try creating a selection set by iterating the drawing db (if you know what you're looking for) but I'm not sure you can 'Editor.Command()' with an in memory database as it's not related to a Document that has a pointer to the Editor.
I don't know if you can edit a Document in memory, someone might have more insight here.
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...
doc = Application.DocumentManager.Open(dwgFilePath, false));
doc.SendStringToExecute("....", true, false, true);
...
doc.SendStringToExecute("close\n", true, false, true);