Be aware that IKE debugs are written to different files depending on which version of IKE is in use. IKEv1 is ike.elg, IKEv2 is ike2.xmll usually, but could also be legacy_ike2.xmll. If you are opening the correct file(s) my guess would be some kind of output format change in the debug that ikeview does not understand, particularly if you are running the more recent versions of gateway code that moved the IKE negotiation function out of the very old vpnd and into the new iked.
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