Linux – XMonad, spawn mutliple terminals on startup on different workspaces

Is it possible to spawn multiple terminals on startup on different workspaces?
I have a bunch of terminals and Firefox which I would like to have running on startup. XMonad places Firefox correctly, but places all the terminals in one workspace. Why is this happening? If my approach is not possible, is there another one? Thank you for your help.

Here is the important part of my XMonad.hs:

main = do
       xmproc <- spawnPipe "/home/x/.local/bin/xmobar /home/x/.xmobar/.xmobarrc"
    xmonad $ ewmh $ defaultConfig
  --  { manageHook          = manageDocks <+> manageHook defaultConfig <+> manageSpawn       -- myManageHook  
  --  { manageHook          = manageSpawn <+> manageDocks <+> manageHook defaultConfig       -- myManageHook 
      { manageHook          = manageDocks <+> manageSpawn <+> manageHook defaultConfig       -- myManageHook 
      , layoutHook          = myLayout
      , handleEventHook     = handleEventHook defaultConfig <+> docksEventHook
      , logHook             = myLogHook xmproc
      , modMask             = myModMask
      , terminal            = myTerminal
      , workspaces          = myWorkspaces
      , startupHook         = myStartupHook
      }  `additionalKeys` myKeys

 myLayout = avoidStruts $ layoutHook defaultConfig

 myWorkspaces :: [WorkspaceId]
 myWorkspaces = ["1:system", "2:network", "3:browser", "4:work1", "5:terminal", "6:work2", "7:files", "8:tutorial", "9:music"]

 myModMask = mod4Mask
 myTerminal = "gnome-terminal"

 myStartupHook :: X ()
 myStartupHook = do
                setWMName "LG3D"
                setDefaultCursor xC_left_ptr
            --  spawnOnce "redshift -l 40.7142:-74.0064 -t 6500:4800"
                spawnOnce "feh --bg-scale Pictures/los.jpg"
                spawnOnce "stalonetray --dockapp-mode simple -c ~/.xmobar/.stalonetrayrc"
                mySpawn "1:system"   "gnome-terminal --tab -e \"/bin/bash -c 'htop; exec /bin/bash -i'\""
                mySpawn "1:system"   "gnome-terminal --tab -e \"/bin/bash -c 'dmesg -TL --follow; exec /bin/bash -i'\""
                mySpawn "2:network"  "gnome-terminal"
                mySpawn "3:browser"  "firefox"
                mySpawn "4:work1"    "gnome-terminal"
                mySpawn "5:terminal" "gnome-terminal"
                mySpawn "6:work2"    "gnome-terminal"
                mySpawn "7:files"    "gnome-terminal --tab -e \"/bin/bash -c 'nnn; exec /bin/bash -i'\""
                mySpawn "8:tutorial" "gnome-terminal --tab -e \"/bin/bash -c 'vim tutorial.txt/; exec /bin/bash -i'\""
                mySpawn "9:music"    "gnome-terminal --tab -e \"/bin/bash -c 'cmus; exec /bin/bash -i'\""


mySpawn :: String -> String -> X ()
mySpawn workspace program = do
                            --spawn program   
                            --windows $ W.greedyView workspace
                            spawnOn workspace program