It seems to be tall task. I don't have resource to perform brute-force, but i have few thoughts.
1. It's possible the wallet.dat is encrypted twice (by Bitcoin Core and TrueCrypt).
2. Aside from hint you've shared. Do you remember how long is the password and which character you use?
3. If your password has relative small amount of possible combination, it can be brute-forced with modern high-end GPU. For example, RTX 4090 has speed ranging from 100 to 3500 kH/s depending on encryption type you use. Benchmark link (not mine),
https://gist.github.com/Chick3nman/32e662a5bb63bc4f51b847bb422222fd.
Assuming that the wallet.dat file is really yours and that you didn't bought it in the hopes of finding the password (who locks almost 3 bitcoin without noting down the password ?), I really don't see how you can achieve this.
Using TeraCrypt is non-standard approach, so i doubt OP is lying. Besides, Teracrypt was discountined on 2014 where Bitcoin price was about few hundred dollar which isn't big money for people who live on developed country.