H!b Transfer

[RQL266]

HI , I am working in Company A on H1b and 2 months back i got offer from company B and my H1b was approved but I din't joined the company"B" because of some issues.Now,I got offer from another company C and they have asked for documents to transfer my H1b,.But when i was going through documents they have asked for all the approved i797 and unfortunately i dont have i797 for company B( i have reciept number).

Will that create any problem in current transfer and is company B i797 mandatory?
Do i need to say company C bout my last h1b transfer details or shall i hide it?

Please respond!!