Unable to get confidence intervals using broom for a gamlss model with a sigma.formula term

I am fitting a gamlss model with the call:

model <- gamlss(formula = formula("y_variable ~ image_name + random(biological_source_name) - 1"),
       sigma.formula = formula("~ biological_source_name - 1"),
       family = "NBI",
       data = na.omit(data))

However I get an error when trying to get the confidence intervals using broom::confint_tidy:

confint_tidy(model)

The message is:

Error in UseMethod("family") : 
  no applicable method for 'family' applied to an object of class "NULL"
In addition: Warning message:
In vcov.gamlss(object, robust = robust) :
  Additive terms exists in the  mu formula. 
  Standard errors for the linear terms maybe are not appropriate

However I get a different error when trying to use broom::tidy:

broom::tidy(model)

The message is:

Error in data.frame(..., check.names = FALSE) : 
  arguments imply differing number of rows: 0, 73

When I fit this model without a sigma.formula term, I am however able to get the confidence intervals.

model_no_sigma <- gamlss(formula = formula("y_variable ~ image_name + random(biological_source_name) - 1"),
       family = "NBI",
       data = na.omit(data))
broom::tidy(model_no_sigma) # Does produce CI output

Unable to get confidence intervals using broom for a gamlss model with a sigma.formula term