OP I am sure you don’t talk about “top 30 universities” in front of your DD but I would advise you not to think like that at all. Top 30 for what? Even if you mean top 30 for Comp Sci – some of the ones your DD could get into are certainly in the top 30.
If you mean the top 30 overall in that table – well firstly, so what? That doesn’t mean a uni outside that 30 is no good. I note that both Nottingham and Cardiff, two respected RG unis, are below the 30 mark. I also note that Loughborough, at number 10, offers comp sci degree with a standard offer of AAA anyway. Maths is needed so it’s off your list, but still it’s there, so yes, AAA can get you into a “top 30” uni for comp sci.
AAA PG or even better actual grades are great, and will for sure open lots of doors. Yes, @TotalOverhaul for some subjects AAA will get you in more or less anywhere (excl Oxford and Cambridge) – MFL or maybe Eng lit for example. But comp sci, like economics and medicine, is very popular and unis can ask for higher grades. It’s just how it is. Doesn’t downgrade your DD’s efforts (or those of anyone gaining AAA).
FWIW my DS2 is at Lboro (number 10! And ranked in top 30 for his subject) with AAB. It’s not as simple as AAA = entry everywhere, and never will be. Equally it’s not the case at all that AAA closes the door to the top unis. It really doesn’t.
Anyway .... all of that is not truly relevant to your DD's situation. There are some great options suggested on here. I'm flying the flag for the underrated Leicester - which btw is less than an hour from London on a non-stop train.
If she is interested in Nottingham and you can’t get to the open day, you can go along and look round the campus and the city at any time. In 2020 DS2 was applying and this was pretty much our only option. Not ideal but it gave him a steer.