I wasn't able to find Manjot and Summer's house! Turns out there are two Hounslow train stations (one underground and one above ground), so I was at one while the taxi driver was trying to find me at the other one! Summer was incredibly helpful and tried very hard to help me get to her house; but my phone battery died and I ended up going to a hotel. She even sent her husband out to look for me! I am very grateful for the effort they went to and hope to meet them some day to say thank you in person.