GADURewardedInterstitialAd.h not found when build in xcode

1. Build from Unity succed but with error that failed to install cocoapods (can be negated if set in ios resolver settings Cocoapods Integration to None)

2. Result export does not contain .xcworkspace file, which can be generated with manual invocation of pod update/ install with the terminal pointing to the folder. (need to change swift version in .xcodeproj / target/ build settings/ swift version from "5.1 5.0" to "5.0" or "5.1" , otherwise won't generate .xcworkspace)

~ pod update/ install come with warning like so:

[!] The `UnityFramework [Release]` target overrides the `LD_RUNPATH_SEARCH_PATHS` build setting defined in `Pods/Target Support Files/Pods-UnityFramework/Pods-UnityFramework.release.xcconfig'. This can lead to problems with the CocoaPods installation
- Use the `$(inherited)` flag, or
- Remove the build settings from the target.

3. (Error phase) Building in xcode from xcworkspace, will fail with error GADURewardedInterstitialAd.h not found, that file is present withing Unity project assets under plugins/iOS/ but doesn't seem to be present in the export files, closest to it is the GADRewardedInterstitialAd.h file in Admob SDK framework files. Same happens for rest of the GADU... headers.

Any answers found relating to this proposing setting header search path to the files location. Which poses two questions in which of all the targets and or projects settings and what is that files location.

Any insight on what I am doing wrong or any suggestions on fixing this, would be highly appreciated.

Unity 2021.1.3f1
ADMob Unity package 6.10
(ADMob sdk 8.8 according to podfile)

 

So turns out the GADU...h files shouldn't be in plugins/iOS folder and were left there from previous installed version of google ads package (5.6). In later package (6.10) are replaced by single file "unity-plugin-library.a".

Still the need for above steps to build is terribly buggy in its own term.