Would looking at XOTL's RAT for the make up of Star League forces in 2750 (34 years prior to Exodus) give insight into which mechs WD would likely have arrived with? This would be:
Light - Thorn, Mercury, Ostscout, Falcon, Spider, Hussar, Firestarter, Hermes, Mongoose, Firefly, Night Hawk, Talon, Locust, Stinger, Spector
Medium - Cicada, Sentinel, Whitworth, Phoenix Hawk, Hunchback, Shadow Hawk, Wyvern, Wolverine (well, not likely given...stuff), Dervish, Kintaro, Crab, Hoplite, Griffin, Kyudo, Osprey
Heavy - Ostroc, Champion, Ostsol, Catapult, Warhammer, Thunderbolt, Lancelot, Helepolis, Exterminator, Guillotine, Marauder, Orion, Archer , Bombardier, Shootist, Crusader, Excalibur, Black Knight, Galahad, Flashman
Assault - Cyclops, Victor, Longbow, Banshee, Striker, BattleMaster, Stalker, Awesome, Thug, King Crab, Crockett, Mackie, Highlander, Pillager, Rifleman, Emperor