I have never seen such a case with selective links not being generated from identical files.
What I can suggest at this point is
1) finding our which are these stylesheets by using this blog post
and comparing the missing resources with the servers that are OK
2) adding these stylesheets in the head section of the page manually. You can obtain them from the [RadControls installation]\Skins folder (where the needed base stylesheets are) and the Skins\[SkinName] for the skin-specific stylesheet. If you need to use various skins you can generate the links in the code-behind according to the Skin property of the control that fails to render them. For this all the skin-specific stylesheets will need to be added in the application.
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