Multi-level Rasch Model Per Douglas Bates' paper

Apologies for not looking this over in 
great detail, but not sure why you're 
mixing lme4 and glmmTMB here??

Sorry, I am not so familiar with all these 
functions ...

Perhaps you mean using glmmTMB::ranef.glmmTMB 
instead of lme4::ranef?  

The easiness becomes similar to page 15:

itypeLeadership itypeLeadership itypeLeadership itypeLeadership 
    -0.39327704      0.35181351     -1.37287890     -0.66120397 
itypeLeadership itypeLeadership itypeLeadership itypeLeadership 
    -1.05406831      0.19744727     -0.81676266      0.35181351 
itypeLeadership itypeLeadership itypeLeadership  itypeTask Sig. 
    -1.17155598     -0.01968142     -0.72344875     -0.70175382 
 itypeTask Sig.  itypeTask Sig.  itypeHostility  itypeHostility 
     0.10980934      0.17308785      0.57989244      2.35224505 
 itypeHostility  itypeHostility  itypeHostility 
     1.34381476      1.64930542      2.37480280

Isn't item easiness just 
lme4::coef(fm2)$item?

Then I get this error: 

Error: 'coef' is not an exported object from 'namespace:lme4'
Execution halted

Best,
Rasmus