Is there a way to change the data type before fetch function in DomoR R Plugin?

I am using the DomoR R plugin to connect to Domo and get the dataset we have in Domo for some analysis. The issue I encounter are:

1. There're lots of warning message after the DomoR::fetch() function:  
   • See spec(...) for full column specifications.
   • See problems(...) for more details.
2. The data which should be a string (character) which looks like 1000.10 will be converted to numeric 1000.1 as the result in the data frame

I would like to know if there's a way to change the data type in fetch function so the data will be correct, also, if there's a way to look at the warning in detail?

Thank you!