score:2
The general rules and compensation tables for delay compensation for Interrail tickets can be found here. https://www.interrail.eu/en/support/delay-compensation
That seems to be straights forward enough as long as all tickets were bought and reservations were made through Interrail.
Note that claims for an "collateral damage" are specifically excluded (as is the case for almost all transportation companies)
Claims for reimburs*m*nt of expenses incurred as a result of sustained delay, e.g. for alternative means of transportation, accommodation, etc., fall outside this policy. Such claims should be submitted directly to the railway undertaking where the delay was incurred
Since this process involves at least two different legal parties (interrail and one or more train operators) expect some finger pointing. You may have to be persistent here.