Yes. I think it is either 1 or 3. If she accepts them she is in an OK place to raise chicks. I would have to move her down to the lower shelf but I think she will accept that.You could probably get chicks in 2 weeks - while 3 is what most people state, I have had hens accept chicks earlier.....can you get some, vaccinated, for 2.5 weeks. At 1.5 weeks old, if she hasn't accepted them - they aren't as fragile, so wouldn't be as much work. If I remember correctly, you have a really good set-up for your chicks.
I'm not saying 'don't ask - just do it', rather I am saying 'Do ask...as opposed to just assuming 'no.' If you can afford it, maybe offer her a bit extra for the effort of looking after the chicks? I am sure she will just love watching the babies grow up.
If you are nervous about them being with Tassels while she is watching them....can you make a good nest for Tassels IN the brooder you have, so momma can care for them - but in a safe place just in case? You wouldn't have to put her in there with them unless there was a bit of a ruckus (probably won't be, but just in case - as a back-up to the back-up).
[So, to be clear
Best option: Tassels take them on and raises them with no issue
2nd option: Tassels takes them on, but you put her and the chicks in the brooder so all are safe and contained - in the case of any issues while you are home/before leaving is when you make the move - not preemptively, mind you.
3rd option: Tassels doesn't accept them and you put just the chicks in the brooder.]
I assume her acceptance or rejection of chicks would be immediate? I mean she wouldn’t mother them for a week and then kill them would she?
Of course I hate that I wouldn’t be there, but that is just selfishness!
My alternative is just to wait until a bit later in the season. Her pattern last summer was to lay 5 eggs and then go broody again all summer. June/July babies would be nice!