I just went through my switches as we upgraded last year, and my devices are similar and have close MAC addresses with consecutive 5th Octet and they are not being combined. You may want to email support to see if they can help.
In Scanning Setup do you have "Merge Windows computers based on serial number and model only (not MAC address)" enabled? I can see that being an issue too. https://www.lansweeper.com/knowledgebase/windows-rename-detection/