Unfortunately, this is a different "package/product" and a slightly different issue, which has been resolved in newer versions of NDK. The quickest workaround that I can suggest is to go into ndk_2_21_01_38\eclipse\features\com.ti.rtsc.NDK.product.ui_2.21.1.38\META-INF directory and delete all files except "MANIFEST.MF" file. Then repeat for com.ti.rtsc.NDK.product_2.21.1.38 directory and also the same thing for two directories under "ndk_2_21_01_38\eclipse\plugins". Those files contains some SSH keys that have not been generated correctly. You will get a warning about unsigned content being installed, but you should be able to install it.
Martin