MailMerge.ExecuteWithRegions - Object Reference Not Set To An Instance Of An Object

We have a document that generates an error in ExecuteWithRegions that we cannot seem to figure out. The error is data driven, in that it happens in some cases and not in others.
The stack trace is pasted below. The document and the offending data set in Excel form is attached.
Can you see if this is either a bug in ExecuteWithRegions or if there is something that could be done differently with the document?

at x4adf554d20d941a6.x6d3ade29d016f4ea.x209132eac59b91dd(x56410a8dd70087c5
x3bdd6d9796b259c5, xf0b374f4c0172a4c
x268076ae4d2d65dd) 
at x4adf554d20d941a6.x6d3ade29d016f4ea.x58c64f348653f92a() 
at x4adf554d20d941a6.x6d3ade29d016f4ea.x5f6867bc5a977cb1() 
at x4adf554d20d941a6.x6d3ade29d016f4ea.xc3819e13f60dd8e6(xf6937c72cebe4ad1 x311e7a92306d7199, Int32 xbfb9ad5ef64f6dc5) 
at x4adf554d20d941a6.x20de8d9377d7de69.xc3819e13f60dd8e6(xf6937c72cebe4ad1 x311e7a92306d7199) 
at x4adf554d20d941a6.x09e62a55cab70965.x5de571cf1cd1652c(xf6937c72cebe4ad1 x311e7a92306d7199) 
at x4adf554d20d941a6.x09e62a55cab70965.xc3819e13f60dd8e6(xf6937c72cebe4ad1 x311e7a92306d7199, Int32 xcd3a9f82634fe5f9) 
at x4adf554d20d941a6.x71da84fff8849445.xc3819e13f60dd8e6(x53cb1139c5c64ee6 xd7e5673853e47af4, Int32 xcd3a9f82634fe5f9, Boolean x3175070523842c98) 
at x4adf554d20d941a6.x4ddd0723770f9758.xb47a6df2eae4ba51() 
at x4adf554d20d941a6.x4ddd0723770f9758.xc3819e13f60dd8e6(x3d1ad8ce75f0db3a xd3311d815ca25f02, Int32 xd284dd7d525c5491, Boolean x3175070523842c98, Boolean x4097fa47409be495) at x4adf554d20d941a6.x3f7228e953be72ed.xd79114a9e7bc0d9e() 
at x4adf554d20d941a6.x3f7228e953be72ed.xc3819e13f60dd8e6(x852fe8bb5ac31098 xe3e287548b3d01f5, Int32 xd284dd7d525c5491) 
at x4adf554d20d941a6.x4af2add38e634ad4.xcbc2273143eac9ec(x852fe8bb5ac31098 xb6842aa1e60562e1) 
at x4adf554d20d941a6.x4af2add38e634ad4.xc3819e13f60dd8e6(xc7f90d9c7c51cede xbbe2f7d7c86e0379) 
at x4adf554d20d941a6.xea876d525d28ff96.xc3819e13f60dd8e6(x398b3bd0acd94b61 xd7e5673853e47af4) 
at x4adf554d20d941a6.xac6c82c74ce247fb.xc3819e13f60dd8e6(Boolean xfad304b5f8f3bb5b) 
at x4adf554d20d941a6.xa268fdb9ca040dde.xc3819e13f60dd8e6(Boolean xfad304b5f8f3bb5b) 
at x59d6a4fc5007b7a4.xcde671c53995c411.xd9db07500873ae98(Document x3664041d21d73fdc, xdeb77ea37ad74c56 xdfde339da46db651) 
at xfbd1009a0cbb9842.x2de8d443b21560d5.xa20689e5bf116840() 
at xfbd1009a0cbb9842.xbf9ddf72e1283af9.x18dfca7c5fd2402f() 
at xfbd1009a0cbb9842.xfedf115fd9c03862.xdd6cf0348a23f220(xcf417e2db4fe9ed3 xe00c282e1a49fcfb) 
at xfbd1009a0cbb9842.xfedf115fd9c03862.x118a2acc122f2bb3() 
at xe86f37adaccef1c3.xc5c3f438428cb03b.xdeeb682062ef79a5() 
at Aspose.Words.Reporting.MailMerge.ExecuteWithRegions(IMailMergeDataSourceRoot dataSourceRoot)
at Aspose.Words.Reporting.MailMerge.ExecuteWithRegions(DataSet dataSet)
at KCMS.DAL.MailMerge.MakeASingleFile(Object FileNumberOrReferralId, DataSet& dsMerge, String rootUncKey, FileInfo templateFileInfo, String dateTimeSuffix, String separateDocID, String documentCategory, String includeInCourtTransfer, String eventCode) in c:\inetpub\wwwroot\Pbk\App_Code\DAL\MailMerge.cs:line 1273 
at KCMS.DAL.MailMerge.CreateCaseDocsFromEvent(String TemplateFile, String FileNumber, Decimal EventSeqNo, DateTime EventDate, String DocketCode, DateTime DocketDate, Boolean IncludeCodefendants, String documentCategory, String witnesses, Int64 ProgramSequenceNumber, String SubpoenaFlag, String includeInCourtTransfer, String eventCode) in c:\inetpub\wwwroot\Pbk\App_Code\DAL\MailMerge.cs:line 452 
at Core_EventEntry.AddCaseEvent() in c: \inetpub\ wwwroot\ Pbk\ Core\ EventEntry.aspx.cs: line 2351
at Core_EventEntry.btnAddEvent_Click(Object sender, EventArgs e) in c: \inetpub\ wwwroot\ Pbk\ Core\ EventEntry.aspx.cs: line 736

Hi Joe,

Thank you for inquiry. I’m afraid. I could not reproduce this problem on my side. First off, please try to use the latest version at your end and see if it resolves your issue. Moreover, I will suggest you to follow up documentation instructions here. If it still doesn’t resolve your issue then please share code snippet for further investigation.