ANT Migration Tool deployment error: "Bad file: XML document structures must start and end within the same entity"

Question

I know what this error means, but the XML I'm deploying (below) was generated by the Migration Tool after running ant retrieve, and every XML validator I've tried says it's valid XML, without typos. I've used this same process to deploy a thousand times, and this is the first I'm seeing of this error (when it hasn't been the result of my manual modification of the package.xml manifest file).

Could this be an issue with the Migration Tool or Salesforce Metadata API?

<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
    <types>
        <members>Campaign.Affiliate_Firm__c</members>
        <members>Campaign.Audience__c</members>
        <members>Campaign.Commentary_Compliance_Code__c</members>
        <members>Campaign.ESG__c</members>
        <members>Campaign.Email_Compliance_Code__c</members>
        <members>Campaign.Email_Strategy__c</members>
        <members>Campaign.Email_Web_Link__c</members>
        <members>Campaign.Fact_Sheet_Compliance_Code__c</members>
        <members>Campaign.Foreside_Compliance_Code__c</members>
        <members>Campaign.Is_Parent_Campaign__c</members>
        <members>Campaign.Social_Media_Post__c</members>
        <members>Campaign.SubType__c</members>
        <name>CustomField</name>
    </types>
    <types>
        <members>Campaign-Campaign Layout</members>
        <name>Layout</name>
    </types>
    <types>
        <members>Edit_Campaigns</members>
        <name>PermissionSet</name>
    </types>
    <types>
        <members>Admin</members>
        <members>Admin Team</members>
        <members>Aristotle System Admin</members>
        <members>Compliance %2F Finance</members>
        <members>Distributor - Institutional</members>
        <members>Marketing</members>
        <members>Operations</members>
        <members>Power User - Modify All Objects</members>
        <members>Sales - Advisory</members>
        <members>Sales - Institutional</members>
        <members>System Administrator API Only</members>
        <name>Profile</name>
    </types>
    <version>45.0</version>
</Package>

Answer 1

Ok, so it turns out the error message was a bit misleading. The XML formatting error wasn't in the package.xml file as the message suggests, but in my destructiveChangesPost.xml file.