Normally I'd speculate about the weather and temperature and pacing and what not, he ran a 12:35 5k in non-ideal conditions though.
I don't think we'll see a sub 26 simply because I don't think he'll be aiming for it. His main focus will be on breaking the WR, just as he was probably capable of 12:30 or better in Monaco but he simply went for the WR rather than risking a monumental blow up.
If he's up for the task and they can get pacers for a 5k of 13:05-13:10 the record is probably his to take. Plus maybe Wavelights but he pretty clearly ignored them in Monaco.
What's scary is the 5k was a relatively weak event for him in the past with the 10k being his obvious forte, so who knows what his 5k form means for the 10k? I do think there is a possibility of the first 25:xx ever...
Plus if Kamworor or Kipruto is in the race to give him a challenge instead of just a race against the clock...