My Norwegian resources are somewhat limited, but I did find "renhold" in one dictionary, and the meaning of this was given as "cleaner". So I would expect "renholder" to mean cleaners. However, the ë is strange, for that is not a letter in the Norwegian alphabet, unless it exists in one of the many dialects. It could also simply be someone's name, or maybe even some sort of brand. Anyway, does "cleaners" make any sense in your context?

It could also be the present tense form of the verb "at renholde" meaning " to keep clean".

I searched for "Renholder" in AltaVista and checked each resultant site until I found one to do with music ("A Perfect Circle"), where the word was actually spelt with the modified "e". The site gives the English title of the album as "Janitor".

Here is another suggestion: "holder" can aslo be a "keeper of", and "ren" may be a popular abbreviation of "rensdyr" which means reindeer - so a "keeper of reindeer" . . .

Renholdër means "Cleaner" or "cleaning Lady", i.e. a person employed for the purpose of providing "Cleaner Services". However, this person most often will be named "regjøringsassistent" in Norwegian, then employed by a "Cleaning Service", as these services generally are outsourced in most cases.

The "ë" must be inspired by others in the Music Business, using strange spellings in their names to stand out from the crowd, like "Mötley Cruë" or "Motörhead", as the ë is NEVER used in any Norwegian word, unless it's a case of discerning two vowels from one another, like in "Citroën".

I hate to have to say it, but the hint you got that "renholder" might depict a "Reindeer Owner" is totally wrong, unfortunately - This person (Chiefly a person from the Sámi people) would be a" Reineier", as Reindeer is spelled "Rein" in contemporary Norwegian. "Ren" would be some rather archaic "upper class" language from some 50-100 years back in time.