help with an ailing laburnum

Good morning everyone, my first post on this forum!
My friend has been asking me for some advice. She has a laburnum which is ailing dreadfully, after a good spring. Photos attached. There doesn't seem to be any sign of pests, or fungus, and if she snaps a twig is it still green inside. I suspect it is suffering as a result of last year's drought, but I would welcome any other thoughts. Also I dont know what to advise her to do if it is in severe stress. Can anyone help? Also although I havent seen the laburnum, looking at the photos it looks as though it's between a rock and a hard place anyway, ie near both a wall and a building, so would struggle for water at the best of times?

 

Would need to see the tree in real life, but it looks like twig blight, its common in wet years, its the only thing I can think of that discolours the branches, it is fungal, so a copper drench and pruning out the discoloured twigs, when the dry times come, apply a high nitrogen feed fortnightly for 2 months.