Looking ahead, the IRB have agreed players need only be released for 35 days prior to the first game of the World Cup, which for Scotland is September 10.
With this meaning that Scots in the Premiership could face finishing their season in May and not being able to join up with the World Cup squad until August 6, Robinson is justifiably concerned.
He said: "What really frustrates me is the spin that's coming out from the PRL (Premier Rugby Ltd), that it's for welfare issues.
"If it was welfare issues, then why are a number of players playing for the Barbarians and why were players playing last week?
"This rule is only in place for financial reasons. If we had been prepared to pay for the players, then they would have been released. There would have been no issue. But we are not going to pay for players to come.
"As a head coach I have a real responsibility for players' welfare and I'd never put any player in a position where he would have to play if I thought it would affect his welfare. So to say this is in place for welfare is really stretching it.
"That is why we are challenging it. We've asked Gordon McKie (SRU Chief Executive] to look into that. For the autumn internationals and the Six Nations there's not an issue, but there is potentially for the World Cup because it says just 35 days currently.
"These are rules we agreed - it's written down in black and white and we've got to deal with it. But I'm challenging it because I think it's important that we make a representation so we can get some clarity."