I have responded to the other thread regarding the same topic. I would suggest you continue the conversation in a single thread. For convenience, I will paste my reply below as well.
Thank you for reaching out.
I am afraid that Kendo for jQuery MultiSelect does not provide such configuration as allowCustom in Kendo UI for Angular.
I would suggest you take a look at the Demo linked below where adding new items to the MultiSelect widget is demonstrated. As you will see, when a non-existing value is entered, the user could add it to the MultiSelect by clicking a button. To achieve this behavior the noDataTemplate is used.
I hope you will find the provided information helpful.
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