Nope. As I mentioned, Borland was working on their own OOP C language. ZTC++'s success caused them to abandon it and do Turbo C++. I know this because of my conversations with Eugene Wang. And Turbo C++'s success caused Microsoft to do MSVC++, which was quite late to the game.
Before C++, the newsgroup traffic on C++ and ObjC was about the same. The C++ traffic took off after ZTC++ was released.
1. looking at newsgroup programming language traffic over time
2. looking at the release dates of Zortech C++, Turbo C++, and MSVC++
3. looking at the programming magazines of the time and what language/compiler they used
4. looking at the programming magazines at the time and seeing they were all about programming on the PC, not mainframes, and not Unix.