I've raised £500 to to help facilitate my charity hike on the West Highland Way.

Hi all.
I have planned to do a charity hike in Scotland in June 2019 (along the West Highland Way to be more precise), to raise money for a condition which my wife suffers from - chronic migraine. (I have set up a separate page for the charity on JustGiving).
However, 2019 is now also going to be the year that my brother is going to get married - 4 weeks after my hike which is in turn 4 weeks after his stag weekend!And guess who is the best man? Exactly.
This means that expenses for my hike will have to be diverted to his stag weekend and wedding too.
My problem is that because of annual leave restrictions at work I have to do the hike on the chosen week (w/c 10th) in June.Please help me with my predicament and help towards the transports and accommodation too thank your