I suppose it's not a good sign if one of your mogs jumped on the netting
but our chicks, with a good broody, are allowed out and about at about that age ..... they are often pekins and so still relatively small. Our cat, before we took her on, had been largely left for weeks to fend for herself. She is a good little huntress and will bring back fairly big young rabbits in the spring etc. When we first started rearing chickens she did watch them but never harmed any and now totally ignores them.
A neighbour has 3 rescue cats that were complete ferals before she had them. She lets her broodies and day old chicks out and says cats don't touch them.
I think a lot of cats just seem to 'know' and don't take chicks/growers even though they are quite capable of doing so. I suppose some would though.
Could you let them out while you and mogs were around and see what the reaction is?
Cross posted with SG