@Undeadking0001
From when, you are not submitting token as it shows that non payment since several years so lots of arrears and penalty. Immediately check your book that when last token was paid?
Income Tax which you are referring is WHT, yes that is not charged for 10+ years old but lets suppose in 17 years old car, if you are not submitting from last 16 years, they will charge WHT only for that period to date on which your car's age was less than 10 years.
For example, if your model is 2004 and you are not paying taxes since 2005 to 2021.
So, they will charge
From 2005 to 2013/14:
Motor Vehicle Tax + Income Tax (WHT) + Professional Tax
From 2013/14 to 2021/2022:
Motor Vehicle Tax + Professional Tax
Car can easily be transferred to any legal heir when you have Legal heir-ship certificate, simply you & your siblings have to collectively sign on stamp paper/ NO objection certificate/ Agreement that all of you have no objection in transferring the car's ownership to deceased's widow (Your mother)