That's a long time to wait for a response from an ISP..
[ Tbird account ] ??
This is confusing to me. The Tbird program has a master password option - but your ISP wouldn't have that , it is only on your computer when you install Tbird and set a master password..( if you have to type a password to open access to the program.).

So I'm thinking you are calling it Tbird account password... but it is the password for your email account @ISP?? to get the pop mail into the Thunderbird program?
If that is the case, do they have a forgot password option on their website?

You didn't want to attempt the copy/paste from the old Tbird profile into the new installation of Tbird? It seems daunting the first time, but doing step by step it isn't so bad..

But it really will save you a lot of time & headache if it is only the email password you need, the old passwords and all saved emails are saved inside the old profile files..
Unless I am missing something...

how to find saved passwords in thunderbird
https://www.google.com/search?q=how+...ird&gws_rd=ssl