Definitely not true, plenty of my coursemates were muslim and went through third and fourth years.
The closest thing we had to that was one of our coursemate's mum (who was of Pakistani heritage) cried after they told her he was going to work at a certain British missile company, so I'd say the possible career paths are something to think about from an ethical standpoint, whether you're muslim or anything else, as defence work is a pretty good chunk of the possible careers resulting from an aerospace degree. Equally you can go the complete opposite direction and work in renewable energy kind of things or civil aviation or something which can't be used to attack i.e. missile defence systems, but you are reducing your options compared to doing a pure mechanical degree for example.
If I had to guess, either his family told him not to do aerospace, or his citizenship prevents him from working certain jobs in the UK so the university told him that if he were to do a year in industry (typically occurs in your third year) then a lot of aerospace placements would be off-limits.