The Position property is not of type string, but it is enumerable type. When setting the property declaratively on the server, the .NET framework allows you to specify it as a string, yet this is not the case if you try to do so from the code-behind, e.g.
//Server-code - compile time error will occur
RadToolTip1.Position = "MiddleRight";
Even more so, the same is valid for the client-side. The property there is not a string, but a client-side enum, and it should be set as such:
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