My first thought was that a hard drive is virtually impossible to repair. The 'speck' sounds somewhat suspicious, given that the distance between the head and the platter is such that if a particle of smoke gets between them, the head will make contact with the platter, and a 'crash' will occur. Moreover, taking a hard drive apart - unless in a very expensive clean room, which is where they're made - will just allow dust (several times the size of a particle of smoke) to get on to the platter. What I think I'm hearing is that the people you've taken it to are not exactly telling the truth. But, the good news is: regardless of 'speck' or not, it is very often possible to recover data from a hard drive. In summary: I don't 100% believe what they're telling you - but that's not to say you won't get your data back.
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