Before the gov't forced SSA.GOV users to switch to login.gov or ID.me, I used an email/password combo and 2FA was done via an email or SMS. I chose ID.me and set it up more than a year ago.
A few days ago, I tried my original SSA sign on method and it still works. Have you tried the old login method for SSA?
I never use a VPN for access unless I can't get access without it. So far only a Canadian bank forces me to use it.