What date do you want to travel?

As the bus is a replacement for the train, your pass should be valid, but the best thing is to check with either VY.no who normally runs the train

https://www.vy.no/en/customer-service/form/tickets-and-travel-info

Or with https://om.entur.no/reisende/hjelp-og-kontakt/kundesenter who deals with all train companies in Norway.

IF you shun buses-some do it to the point of making detours well over 333KM- then this is indeed a case where a detour on rails is very much longer and time consuming-plus no garantee that there are also no works at all via that route. It goes North-east from G toward Karlstad and then the main line from STOckholm (but double check, somehow Ive seen somewhere there is also something with this direct line). Ttrains on G-O are shared between VY/NO and SJ/SE. There most certainly will not be works along the whole line.

Thanks AnnaB we intend to travel on the 14th July. I'll check out the sites you've provided.

Mcady thanks also for your information ill check which section is blocked on the day we travel

entur.no shows rail replacement buses on part of the journey, operated by Vy. Train tickets (including Interrail) should be valid.