Hi there,
Your situation is really unfortunate and I'm sorry to hear you've ended up in this position. However, I really don't think you need to worry.
When I started uni we had an international flatmate whose flight from her country was delayed for several days, meaning she missed more than half of Freshers. However, as soon as she arrived we all welcomed her into the flat, added her to the group chats etc and she ended up settling in really well and having a great time at uni after Freshers' week.
There is a lot of pressure on new students to 'live their best life,' make lots of friends and have tons of fun in Freshers' Week, but its really not the be-all and end-all. There will be loads of opportunities to get to know people, experience the fun side of uni and find your feet throughout your time at uni, so if you miss most of Freshers, although it feels dreadful at the moment, it really won't be a problem for your uni experience in the long run 🙂
Hope this helps, best of luck 🙂
University of Bath