If you're going to be a 'fixer' for cash - and not that much either - then you definitely have to make sure you don't get your jeans singed in the conflagration you've created, nor should you dump them in a nearby bin. Incidentally, I am rather surprised you did not notice you had dropped your cell phone in the ruins, during your haste to depart the scene of crime.
Is it any wonder than the law caught up with you and your mates, and rather swiftly too. You could hardly deny the phone was yours, but you did. You even said that you'd lost it and someone else must have dropped it at the site of your criminal activities.
The jeans...well, it was a bit difficult wriggling out of ownership of those. There were some tell tale signs of burns on your legs, in the same places where the jeans were 'singed,' and by the way, your DNA was all over the inside and outside of them.
You, your mates, and the guy who paid for the job, got your just desserts.