ID required please - grassy thing

I have a self seeded cordyline; despite never wanting a cordyline, as here on the "English Riviera" they're in every other garden.
So what happened? It snuck in and hid in a clump of Iris foetidissima until it was about two ft tall, then 3 or 4 years ago I removed the stinking iris and decided to give it a chance it's now about 7 ft tall.

 

I just checked the rest of the garden and didn't find any more, so it's quite odd - three of them in the same small area and no others. I just googled to see if birds eat the fruits and apparently they do, so that might be it - the result of one big bird poop. I don't think they'll enjoy that location though as it's dappled shade and quite damp too, when we get normal amounts of rain. So I plan to dig them up and try them in pots - they are quite attractive, and I can happily dump them when they get too big.

 

I’m quite sure that this is not Camassia in your first pictures. Not that I can tell what it is, but I would take out one and see if it has a bulb or roots like a grass or roots like a cordyline.