Is c++ good enough for a WEB based ERP

Our company recently order a new ERP ( including Accounting , HR and BI complete solution ) Program . Now some engineers accept the work and submit their solution will be build via C++ and FIBER database , they also grantee to developing both IOS/Android apps , complete web site and any thing else we need . therefore they said Application and it's database must be in single server.

I hear some bad news about developing Web-Apps in C++ , Is it True or not ? Is it true C++ will use more resource than other Modern-Languages in web purpose ?

thanks in advance to who will enter her/his opinion to this topic .