Hi OP, I'm so sorry that you've had to deal with such an awful person, and it does sounds as if something needs to be done about the manner and tone he used with you. I'm not at all expert in HR and policy, so will leave other well informed posters to advise you on that.
However, I am a fluent spanish speaker and have lived in Spain for over 20 years in total, so I can offer some insight into his use of the word "coño" (I am assuming this is the c-word he used).
Culturally in Spain the use of this word is very common in street talk. I remember the first time I ever heard it used (actually used by a very nice old lady who lived near me) and I was shocked to hear her use it because I was hearing the literal meaning, which is, as you've said, referring to female genitalia. However I then learned to appreciate that it is used to express a variety of things ranging from disgust to suprise, and even in some cases, appreciation or pleasure.
Spanish use that word in the same way we might say damn, eg damn that's bad but we can also say damn that's good. It can also be used as we would use the words shit or hell. So I doubt he was actually calling you personally a 'c**t', but was using it to say something (a process or an overall procedure) was shit, or was fucked up. However I caveat that by acknowledging that only you heard the words he said and only you will know for sure if he was using it as a direct personal insult, or in the way I just outlined.
But I would say while it is often used, it is considered vulgar and is generally not acceptable to be used in a business or professional setting. So whichever way it was used, I do think attention needs to be drawn to his manner and conduct as it sounds deeply unprofessional.
So sorry you had to experience it.
Edited for typos and spelling