It is difficult to see what is going wrong without the data counts.
However in the Y ~ BB(n,mu,sigma) distribution model, Y|p ~ BI(n,p) where I believe p ~ BE(mu, [sigma/(1+sigma)]^0.5). [Note that sigma lies between 0 and infinity, while [sigma/(1+sigma)]^0.5 lies between 0 and 1.]
So in your intercept model, p ~ BE(0.501,0.328) which may be more reasonable.
To sort out the error messages from your model with time, I suggest you email the developers of gamlss directly, ideally with the data counts.