Hi , the campaign scenarios run with mods that disable or change the allowed vehicles in the scenario you would need to edit these . Eg for mission 10. in file

F:\SteamLibrary\steamapps\common\Transport Fever 2\mods\urbangames_campaign_mission_10_1\res\scripts






restree = {
models = {
model = {
vehicle = {
train = {
usa = {
["alco_pa_front_v2.mdl"] = modifier.util.availability(missionstart, nil),
["alco_pb_back_v2.mdl"] = modifier.util.availability(missionstart, nil),
["heavy_mikado_v2.mdl"] = 1,
["milw_ep_2_v2.mdl"] = 1,
["milw_ep_2_v2.mdl"] = 1,
["class_9000_v2.mdl"] = 1,
["alco_hh600_v2.mdl"] = 1,
["hiawatha_v2.mdl"] = modifier.util.availability(missionstart, nil),
["class_prr_gg1_v2.mdl"] = modifier.util.availability(missionstart, nil),
["bigboy.mdl_v2"] = 1,
default = modifier.util.disable,
}
},
waggon = {
usa = {
["parlor_v2.mdl"] = 1,
["pullman_1900_v2.mdl"] = 1,
["streamlined_santa_fe_v2.mdl"] = modifier.util.availability(missionstart, nil),
["gondola_1907.mdl"] = modifier.util.cargotypes({ "SAND" }),
["stake_car_1895.mdl"] = modifier.util.cargotypes({ "STEEL", "PLANKS" }),
["boxcar_1902.mdl"] = modifier.util.cargotypes({ "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
default = modifier.util.disable,
}
},
bus = {
usa = {
["schneider_pb2_v2.mdl"] = 1,
["twin_coach_v2.mdl"] = 1,
default = modifier.util.disable,
},
default = modifier.util.disable,
},
tram = {
usa = {
["peter_witt_streetcar_v2.mdl"] = 1,
["pcc_1643_pittsburgh_v2.mdl"] = modifier.util.availability(missionstart, nil),
default = modifier.util.disable,
},
default = modifier.util.disable,
},
truck = {
usa = {
["ford_m77_universal_v2.mdl"] = modifier.util.cargotypes({ "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
["ford_m77_stake_v2.mdl"] = modifier.util.cargotypes({ "STEEL", "PLANKS" }),
["mack_ac_universal_v2.mdl"] = modifier.util.cargotypes({ "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
["mack_ac_stake_v2.mdl"] = modifier.util.cargotypes({ "STEEL", "PLANKS" }),
default = modifier.util.disable,
},
default = modifier.util.disable,
},
ship = {
["ds_schaffhausen_v2.mdl"] = 1,
["zurich_v2.mdl"] = 1,
["klondike_v2.mdl"] = modifier.util.cargotypes({ "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
["votrans_universal_v2.mdl"] = modifier.util.cargotypes({ "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
default = modifier.util.disable,
},
plane = {
["dornier_b_merkur_v2.mdl"] = 1,
["junkers_f_13_v2.mdl"] = 1,
["junkers_ju_52_v2.mdl"] = modifier.util.cargotypes({ "PASSENGERS", "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
["douglas_dc3_v2.mdl"] = 1,
["douglas_dc4_v2.mdl"] = 1,
["douglas_c49_skytrain_v2.mdl"] = modifier.util.cargotypes({ "SAND", "STEEL", "PLANKS", "PLASTIK", "FOOD", "ALCOHOL", "TOOLS" }),
default = modifier.util.disable,

Complicated fix, but I'll take it! Is just deleting those lines enough?

There is one level in Act 3 that allows the player to use the official USA passenger vehicles of the present day.

In the Canada Oil sands mission you can choose to build and run passenger trains between the towns, although running trains is not part of what you do for the mission tasks primary or optional. They're simply there if you want to use them to make money to keep you afloat to complete the mission.

Of course the official game has a lot of vehicles missing from all over Europe, Asia and North America (especially the trains of Britain) so the modders have taken it upon themselves to fill in many of the gaps left by the official game.

There is still however no QJ class or SY class steam engines mod much to my saddened heart.