if somebody can offer encouragement why I shouldn't consider re-homing as a scary thing, it would be greatly appreciated

I'm sorry that you're having so much trouble with all of this. In the end you will have to figure out what will work best for you and do that.

Rehoming IS scary and there's no way around that. It will help if you can get to know the new owner well enough to feel that they're a good person who will provide a good home, but that's not always possible.

thank you.
Another problem is that in my situation there need to be several new owners. even if each person takes in 2 birds from me, it totals 4 new owners

Then, I think rehoming, at least some of them. My situation is very different. I live alone, have one grown, married daughter and no grandchildren.

Don't focus on how many you have to rehome. Just start the process.

I was thinking to have no rehoming fee (and I wouldn't advertise them on sites "birds for sale") because I understand that the new owners would be spending (hopefully) good amount of money on my birds. but I just realized what if somebody pretend they are happy to adopt my birds and then they sell them for profit individually? (you know , even some bird people think mostly "profit" )
I can have them sign a waiver that they adopt not for resell but it probably won't have any legal power

I would say go on your instincts about the person. I don't have experience, but I would think not many people would get a bird to resell it.

well if the person is a breeder and there are 8 free cockatiels available, you can possibly make some profit.

But you are right

Maybe don't list eight at once. Start with one or two: the ones you most wouldn't miss,

It's usually recommended to charge some kind of fee, for the safety of the animal. Sometimes people who take free pets are doing worse things than reselling them.