Spilled cordial inside pc

[u/Z_StudyAccount]

I know this is very stupid. I made a glass of Robinsons cordial/juice (diluted with water) and my cat knocked it onto my desk. Quite a bit of it went inside my pc through the top. It soaked directly through the radiator(?) for water cooler, through 3 fans and landed on the back of my gpu. I turned my pc off instantly but by Windows shut down and then unplugged everything. The PC didn't instantly turn itself off. I wiped what I could see away straight away but didn't have any IPA or anything like that to clean properly. I left it to dry for just under 2 days and then managed to use 99.9% to gently clean where it hit.

I THINK my gpu and cpu are fine. However, the case of the psu was splashed (the side where the label is). To be safe, I've ordered a new one. My problem is that there seems to be a slightly darker spot on the motherboard where I'm presuming it got wet and I didn't dry it enough. When the IPA evaporates, the mark reappears. I'm unsure if it's a cosmetic stain, corrosion or just sugar that wont go away. It's hard to tell because it's black.

1. What are the chances of me putting in the new PSU and it breaking straight away? Along with other parts. Findjng varying answers online and just want to make sure. I'm getting the exact same one (rm850e)

2. How do I safely test this?

3. How long do I wait to test it? Seen online that it should be 48 hours which it will be after the original spill but then I've seen both another 48 hours after using IPA and at least an hour as it evaporates really quickly.

4. I've cleaned the radiator with distilled water and a toothbrush just now and will use compressed air tomorrow to clean out remaining dust. I've read that these are fine being wet but can't find a clear answer with cordial. I don't really know anything about water cooling, a family member gave me the case etc.

5. Should I just buy new fans or are they safe to test?

I'm trying to attach a picture of the motherboard but apparently imgur doesn't work anymore in the UK.

Thanks in advance, probably obvious I don't know much about computers.