我见过有在ADDITIONAL的那篇ESSAY里提推荐人的 (就是提ANY OTHER INFO YOU WANT THE ADMISSION KNOW那篇)..他写的时候是分条条的把他想写的写出来的..就是:1.我的什么什么强...2.推荐人:什么什么..(比如辞职了,原来是担任什么,现在去哪了,联系方式)..3.公司合并了..以前怎么怎么,现在怎么怎么..
you may ask them to write their background in the beginning of the letter as introduction.
sth like: I am "title" at *** company and my relationship with the applicant is ***. My graduate degree was from *** university. I had experiences in ***.
Since you mentioned that you have seen the letter, then it seems not too difficult to ask the recommenders to add sth which is fact-based.