I have worked with the presentation files shared by you and have been able to observe the issue specified. An issue with ID SLIDESJAVA-37332 has been created in our issue tracking system to investigate and resolve the issue. This thread has been linked with the issue so that you may be notified once the issue will be fixed.
The concerned issue has been marked as resolved in upcoming Aspose.Slides of Java 18.10. We will share the notification with you as soon as the product will be shared online.