Ugly shriveled Laburnham starts sprouting

We have a Laburnham about 3 meters tall (long droopy branches). It is horribly ugly and brown and shrivelled. It flowered well in the spring but just deteriorated during the year. Assuming it was diseased we didn't worry about an enormous garden bonfire lit nearby and the boughs were scorched.

Well lo and behold, a month has passed and beautiful healthy leaves have sprouted from the scorched boughs. 

So now I am wondering what is actually wrong with this tree and one looking similar in the front garden. Are they sick and will they recover next year or shall I chop them down?!

I have photos to post but have to work out how first so please bear with me.

Quite excited to hear your diagnosis!