Thanks for considering Aspose.
I've tested the scenario with Aspose.Pdf for .NET 4.1.1 and I'm unable to notice the problem. The resultant PDF is being generated without any issue. I've used the code snippet shared over Performance Improvement while converting TIFF to PDF (Please remove the line of code in which Image scale value is being set). For your reference, I've also attached the resultant PDF document.
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