Peru: lost the certificado de internamiento temporal

[Tommy_boy_31]

I recently bought a bike in Lima, it is registered in California. Unfortunately, the 'certificado de internamiento temporal' (the visa of the bike) got lost when the ex-owner sent me all the papers. So I have the certificate of title that proves that I am the owner, and the contract of transfer signed by a lawyer. I am planning to ride to Bolivia soon and cross the border in Copacabana and I wonder if I am going to be in trouble.
A friend of mine called Aduana, vehicle registration office or something like that, and they said that it was not possible for the ex-owner to sell the bike. But it was possible for the ex-owner to send me an official document signed by a lawyer saying that he allows me to leave Peru with his bike. This document is to be sent by mail and it would take a couple of weeks. The other problem is because I don't have this certificado de internamiento temporal, i dont know by when i have to be out, but I believe its more or less in 2 weeks.
I am thinking about riding to Copacabana, showing that i am the owner and that i lost the certificado de internamiento temporal, and using a bit of US dollars. Anyone had a similar experience recently?