Hi Jack, Thanks for posting here in Microsoft community, I understand how stressful it must be to lose access to such an important account, especially while abroad. Since you've already tried the standard recovery steps multiple times without success, I recommend contacting Microsoft Support directly via this link https://support.microsoft.com/en-us/topic/customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 and requesting escalation.
Clearly explain your situation and offer to verify your identity through alternate means.
Also, if your account was flagged due to unusual sign-in activity from Antigua, it may help to mention your travel history and provide any proof of identity or past account activity.
Simply Escalate to Microsoft Support and request manual verification, avoid repeated failed recovery attempts, as this may further lock the account and prepare identity documents and any past account usage details e.g., frequent contacts, folder names, etc. to support your case.
I hope this helps you out, let me know.
Chard