There is no such build in functionality that to allow loading only the valid part of the settings. This save/load is based on the IStateManager's SaveViewState and we have pretty much no control over it.
In your case you will have to implement another way of saving such settings that to allows you to load only some of them. You can loop the FilterExpression to save it in some custom collection and later to try to recreate valid FilterExpression. Check this help topic about working with the expressions:
All the best,
the Telerik team
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