Yes, that'd be a problem as you're doing selection based off first and last name. The code examples I've provided are using their user id. You should not be storing the selection in the database by first and last name as name is not unique so you could have 5 people with the same name for example. I suggest changing your query select to use the following.
Query:
Code:
SELECT `id`, CONCAT( `firstname`, ' ', `lastname` ) AS name
FROM `#__comprofiler`
WHERE `cb_shac_role` LIKE '%Office%' OR `cb_shac_role` LIKE '%Befriender%'
Value Column: id
Label Column: name
Note all existing selections for that field will lose their values and need to be re-selected. This will then store by id and allow the code examples I've provided you to work fine.