[Tlhingan-hol] Pronoun agreement in to-be sentences

[Qov]

A participant in the Vancouver qepHom has produced the sentence:

nuHwIj nIvqu' 'oH mu'mey'e'

to mean "Words are my best weapon."

The fact that mu'mey does not agree with 'oH is bothering me, but I'm 
not sure if it should. Why doesn't the disagreement "plural are 
singular" bother me in English?

If I have him change it to:

nuHwIj nIvqu' bIH mu'mey'e'

... then I've changed it to "Words are my best weapons."  If it were 
my own sentence I'd do that, or even make it {mu'mey bIH nuHwIj 
nIvqu''e'}, but as it's someone else's sentence I don't want to say 
"it doesn't feel right" or "it has to agree with both" unless there 
is something backing me up. Do we have any canon copula sentences 
with the two parts deserving different pronouns?