1. Can I transfer my H1B from Company B to Company C with out 797 copy? 2. Is there any prob in Visa Status if we do like this?

I recently transfer my H1B Visa from Company A to Company B . Joined Company B after one month of H1 approved for Company B. But I didn't receive my 797 copy from Company B. They are "Saying they didn't received soft/Hard copy from USCIS, we may need to apply 824 for duplicate copy which will take 3-6 months time". Now I don't have I-797 soft / Hard copy with me except receipt number. Now due to some reason I want to transfer my H1B to Company C and join in Company C. I have all other required documents ( Educational, Pay stubs, etc..) except 797 soft/hard copy (Had receipt number). And I have company A 797 and I-94 valid till June 2016. Is it safe to transfer my H1b from Company B to Company C with receipt number only?