If anyone offers to sell their Bitcoin to you simply because they know you one way the other, don't buy from them.
This days it is getting harder to trust anyone.
Proper verification for offline trades is my must. You might not know what your friend is passing through sometimes and the extent he can go to resolve those challenges. But then if we cant trust friends for common transaction then who should we even trust.
This should serve as an example to all beginners, if someone can't buy or sell their digital assets on exchanges, you have the right to be suspicious, teach them how to if you can but don't ever buy from them, it can be stolen digital assets.
As you have rightly stated here, if they intentionally don't want to sell on any exchange and are looking for any means to disburse their coins, then it should be noted as a skeptical move.