fwiw, the big hill he did well on in Croatia was ~4:45 for the Milan group at 6.5 w/kg (for Paaschens, probably around the same for Milan or higher due to his attacks even though he's heavier), which would be well beyond what someone his size would have to do to follow the record time on Poggio providing he was in position at the bottom. Probably putting my neck out here, but if he's allowed to go for himself and in position, I think he can easily exceed the level of climbing Ewan did on a climb like the Poggio.
On the flipside, I could see Bahrain completely ignoring all of that and just having him lead out Mohoric into the bottom of the Poggio, considering his big power, weight and aero position make him perfect for that role.