I've never heard of TIOBE before, and don't know whether it's worth being on their list, but in my opinion:
1. FreeBASIC is a language, FBC is a compiler for it. (In this respect I would disagree with what has been written on Wikipedia.)
It's a language defined in a de facto sense by its implementation in FBC/its runtime libarries, but also more usefully by its extensive documentation, which sets it apart clearly from a generic BASIC implementation.
(That is, in the sense that most/all other implementations of BASIC would not comply with our docs, not necessarily that other BASICs are less well-documented.)
2. TIOBE seem to have well-defined criteria of what is/isn't a programming language (
https://www.tiobe.com/tiobe-index/progr ... #instances), and their rejection is based on one of those criteria, so they've behaved reasonably so far.
Of course, that doesn't mean that they'd accept it based on someone saying: "there, I edited the page to say it's a language", but they might accept that maybe the original author didn't properly consider the distinction between language and compiler, and that it can be corrected by an edit.