While playing a Nunh outside a traditional tribe structure is odd by what we know of lore it is not completely implausible. Just as the Xaela have their own quirks and oddities sprinkled throughout their tribes it is safe to assume the culture of each unique Seeker tribe (And their offshoots) is just as varied. With enough creativity anything is possible, within reason of course.
As for the meat of the question I don't think its RP suicide to RP a character with the title. There will be people who knee jerk and shy away from a Nunh RPer but there are many others who will likely find it interesting or at the very worst not care about the Nunh status. Unquestionably there have been people who have soured the title and treated it as a fetish tool or just thought it out poorly but it has the potential to be so much more than people may give it credit for.
My character as an example is far from how one would consider a traditional Nunh to be. Similar to yours he also more stumbled into the role than sought it out, and takes care not to introduce himself as a Nunh in most cases. In his eyes the title only has meaning to him and the people within his tribe, he does not want to lord around in public like its something to be in awe of. He treats his responsibility to his tribe with the utmost seriousness, which usually leads into bouts of paranoia of not being all he should be for them or that he may be leading them incorrectly. It's been an interesting dynamic for me having to balance N'khai's desire to be a "good" person/Nunh alongside what he sees as a distorted moral compass and upbringing.
Rambling aside: I wouldn't shy away from tackling the challenge of RPing a Nunh. There will be people who will think the worst immediately but that shouldn't stop you from telling interesting stories and promoting a better image for Nunh RPers as you do so.
As for the meat of the question I don't think its RP suicide to RP a character with the title. There will be people who knee jerk and shy away from a Nunh RPer but there are many others who will likely find it interesting or at the very worst not care about the Nunh status. Unquestionably there have been people who have soured the title and treated it as a fetish tool or just thought it out poorly but it has the potential to be so much more than people may give it credit for.
My character as an example is far from how one would consider a traditional Nunh to be. Similar to yours he also more stumbled into the role than sought it out, and takes care not to introduce himself as a Nunh in most cases. In his eyes the title only has meaning to him and the people within his tribe, he does not want to lord around in public like its something to be in awe of. He treats his responsibility to his tribe with the utmost seriousness, which usually leads into bouts of paranoia of not being all he should be for them or that he may be leading them incorrectly. It's been an interesting dynamic for me having to balance N'khai's desire to be a "good" person/Nunh alongside what he sees as a distorted moral compass and upbringing.
Rambling aside: I wouldn't shy away from tackling the challenge of RPing a Nunh. There will be people who will think the worst immediately but that shouldn't stop you from telling interesting stories and promoting a better image for Nunh RPers as you do so.