A roadside axle swap is probably not an option, since you will not likely find a direct replacement. Even if the axle can be repaired on site (welded or patched together somehow) the trailer will probably have to be jacked up, the axle removed, repaired and then reinstalled by someone with the right portable equipment.

Rent the flatbed and get it home. Don't risk the trailer, the glider and possibly your car (and your life!) trying to tow a compromised trailer. And if it breaks free while trying to tow it, you are also putting other motorists at risk. And sending up a big red flag for the circling personal injury lawyers.