now that that is done, after i fixed that, im getting these: this is from going to the next day twice, the first time was with the cattle being locked in, the next they weren't, a few of the errors is because there isn't a restraintype or stress_mod in the save file (i think), but the Invalid operands errors are not
The stress_mod issue likely means an error created while editing save files, as I am not aware of any changes in the mod and the error points to vanilla content. Hopefully you can undo, or have a backup of that save file. Though it's not hard to add it back to the stats dictionary with default value of 1, but if they are still present then the issue is a typo somewhere else.
restraintype should be apart of the expandedfarm dictionary inside the state dictionary. These are the default values, adding any missing should bring save file up to date.
var expandedfarm = {restraincattle = false, restraintype = "none", bottlesprice = 10, bottlesowned = 0, storingpiss = false}
String + Nil for Mansion.gd:690 is a derived error.
The following line appears to be wrong(Edit: expansion.gd:2208): if farmmanager.jobskills.farmmanager == null:
It should be: if farmmanager.jobskills.has("farmmanager") == false:
Nil > int for Mansion.gd:1238 is also derived.
Ah right, with the earlier changes your line numbers don't match my line numbers.
That picture is horrendous, better than no picture but still would prefer a proper screenshot. If you are on a windows system with a keyboard, then the PrtSc key will save the entire current screen to the clipboard and can be pasted into any picture editor(I use Paint to crop the pictures). Alt + PrtSc will produce a screenshot of only the selected window.
Cause of error for line 2209 is in function "getFarmFactors" of expansion.gd (line 2306 for me). It's returning a string, but function "dailyMilking" is expecting a bool. Change the first 2 lines:
var result = str(person.farmexpanded[factor])
if result == "default":
to(1 tab each):
var result = person.farmexpanded[factor]
if typeof(result) == TYPE_STRING && result == "default":
Edit: grammar
"expansion.dailyNPCs" will not work, because "expansion" is not a variable inside of Mansion.gd.
The function "dailyNPCs" exists inside of expansion.gd, and that file is loaded by globals.gd into the variable "expansion". Thus "globals.expansion.dailyNPCs" is a correct path.
Edit: "globals" is not a variable inside Mansion.gd either, but it is specially defined by the project settings to be present in all scripts.
Honestly, it feels like most of your problems are derived from using old save data. It seems that for some reason your person objects don't have a member variable. You will likely need to add the "dietexpanded" dictionary from person.gd to your slaves in the save file. It's strange that they didn't gain it when being loaded, but there is no way to add it to the person objects afterwards. Though you could transfer all the slave's data from objects loaded from file to freshly created objects, it's a fair amount of work.
Now there are these two invalid operands, the top errors I’ve already fixed. Line 2209 says if auto == false: 
edit:or it's because the save has fetish values that are no longer used