To be clear here, “not paying for an interpreter” is absolutely fine!
Welsh-language events which make no concessions for L2 speakers should be the norm, just like English-language events don't generally include a little bilingual section at the beginning to welcome all L2 English speakers.
Like @aran (I think) once said, “there's no such language as Bilingual”. https://toot.wales/@nic/113265553565716448
Nic Dafis (@[email protected])
@[email protected] I just had to Google “CYA”, and it's perfect for this context! “Learners welcome" is often just a nice way of saying “we haven't paid for an interpreter” - but L2 people who wouldn't be able to deal with this particular event would also be unlikely to be interested in it anyway.