Linked multiselect question as roster source

Dear all,

I have a multiselect question asking for participation in programs. Based on that question is a roster where a list question asks for all year(s) in which countries participated in the selected program.

Subsequently, I have created a linked multiselect question asking the interviewer for which program-year combinations she would like to fill out the next section of the questionnaire. I would like to allow for multiple choices and therefore want to create a roster for the different combinations chosen.

However, this is not possible with the linked question being the source and creating a full list with all year- program combinations (75 years, 11 programs) and applying filter conditions also does not seem feasible.

Do you have any suggestions on how to implement such a questionnaire structure?

Thank you for your help!