"Rod" might work as a suitable nickname, since it's also used for names like Roderick (which sounds eerily similar to Rodrigo now that I think about it).
You don't necessarily have to frame it that way. "Hey folks, I understand my name can be difficult to pronounce sometimes so feel free to call me X". But I also totally understand if you don't feel like it's necessary. Just something to keep in mind :)
My approach as well. I’m not bothered with different people pronouncing my name differently. Does not stop me from being pedantic about pronouncing other people’s “correctly” :)
