Searching for objects based on the backend on a string that is defined in the runtime database always has some degree of risk as you never know if the string will match perfectly. Its possible that the issue here is the carriage return in your Xpath string but that just demonstrates the issue with this approach.
A first step to get this logic flow working would be to use the contains() function in your Xpath which can be more forgiving than the = operator. For instance, you could use contains(CompanyName,’SUEZ’) which will grab all company objects with ‘SUEZ’ in the CompanyName attribute. This approach also has some degree of risk to it though, as any company with SUEZ in the CompanyName will be returned.
The most flexible approach here that I would suggest is to select the company directly from the employee detail popup with a reference selector. This way you can just select the company that the employee is a part of unambiguously. Unless you have a specific use-case requirement that would prevent this approach, it is the most flexible approach as you will be able to directly choose which company an employee is in without the need to search for the company in a microflow.
Hope this helps