Attached you will find a Kendo Grid with a MultiSelect column editor that properly submits its selected items to the Update controller action. Note that in order to run the sample, you will have to add the Kendo.Mvc.dll in the "lib\KENDOUIMVC\2020.3.1118.545\" folder. May I ask you to modify that example, so it replicates the issue present at your end and send it back to me? This way I will be able to troubleshoot the case locally and to provide you with the most appropriate assistance.
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