The marauding Samoan prop, brought in from the NRL to bolster their promotion hopes, was forced off after Halifax prop Ryan Boyle’s challenge in the 60th minute.
Nervous Rovers had to battle hard to overcome the Championship part-timers who led until conceding Nick Scruton’s 72nd-minute try.
Sheens was relieved to see his side avoid a shock defeat but the former Australia chief was far from happy action was not taken over the dangerous tackle on ex-St Helens star Masoe.
“He was chicken-winged and I’m sure it will be cited,” he said.
“The touch judge reported it but I imagine he has not been firm enough as it went on report but was not penalised; his shoulder went in and out.
“He may be doubtful for this week against a Super League side (Leigh Centurions) when his experience and size would be much appreciated.
“We’ll wait for the scans but it was fairly obvious so I’m disappointed it was not picked up.
“The game had me on the edge of my seat and I’m sure it did everyone else, too.
“I’m still fairly happy with the overall effort but we’re still tinkering with our halves.
“You can see our last plays and kicking are still not what they should be and we need to fix that big time next week as Josh Drinkwater’s very good for Leigh.”
Halifax coach Richard Marshall was proud of his side’s efforts as Ben Heaton scored four tries to put them on course for back-to-back wins against the promotion favourites.
“We were fantastic defensively and they probably should have scored three or four more tries,” he said. “But we kept turning up for each other, working hard, pushing them back and defending penalties.
“We could only do it for a certain time, though – pure physics dictated that; they are a full-time, professional side with highly-trained athletes and they were always likely to get over the line at some point.”