Good to see you escaped, nobody like hospitals, they're full of sick people and you don't know what you'll catch.
Maybe your neck of the woods is different on some standards, but here the normal white blood cell count is between 3 and 10K, except when you have an immune system like mine which would be able to take on the bastard offspring of Ebola and HIV and laugh at it, because docs have stopped asking me if I have an infection or are sick as my white blood cell count is naturally around the 12K region. Always has been, but with nothing else to show there's something actually wrong inside me they now know I just have a seriously strong immune system.
But 30+k, that's quite an infection and could explain the heart enzymes as, obviously, when you're trying to fight off something like that it does stress the heart and that stress will result in an increased level of such enzymes which CAN be an indicator of heart muscle disease, so maybe more closer monitoring will be the order of the day as tests done when you've got such an infection may give a skewed result and all could well be good with the ticker itself, it's maybe just been the stress on the body from the infection building up, as you say, over a period of time which has triggered it, especially if the abdominal pain has been interfering with your sleep as that will also stress the heart. So don't stress over that, it won't help your heart, they've identified something that MIGHT be an issue but if it WAS an issue then you would have had a battery of tests done and you would likely still be inside the home for the diseased instead of being at your own home where you can be more relaxed.
I'm guessing it's a "nuclear" dose of antibiotics you've been given, so expect stomach issues as the "good" bacteria get killed off too. Ginger, fresh or in capsules or in pills based on ginger, is great for settling upset guts, and is something I always have here "just in case". Ranitidine (Zantac) is a great one for excess gut acid, I found that to be better on me than Omeprazole when I got an NSAID (Ibuprofen, to be precise) induced stomach ulcer, and always have that stuff here "just in case" as well. Just be aware that the antibiotics themselves can cause issues, and if the hospital hasn't given you something to protect against these effects it won't do any harm to have something at home "just in case".
So best wishes, not giving anything on your underlying diverticulitis because only you know what triggers that off and how to control it as you'll have been given more than enough info about it, but what I will say is that since it's Sunday here I was going to start the day off with a more "mellow" tune and, given that you're obviously another "Never let the bastards grind you down" type of person then I don't think I could have picked a more apt track for the first choon of the day if I tried, because the choice was made before I even started catching up with this thread.
Peace, bro, get some much needed rest, especially as the antibiotics will likely knock 7 shades of shit out of you, for everyone will still be here when you wish to have a chat. And enjoy the music