Yes, yyhmail.com can receive emails.
No, yyhmail.com is a throwaway domain and should be blocked.
You can use MailCheck's free API to automatically block throwaway emails. Read our documentation to get started. No registration required.
A record
50.22.218.215
MX records
mx00.gmx.com
74.208.5.4
mx01.gmx.com
74.208.5.27