The Reform leader has previously said there are too many SEND diagnoses for children.
The former PM's call for a change of course is rejected by Downing Street but welcomed by the Tories and Reform.
Brendan Cox, whose wife was killed in 2016, says the band's response was "half an apology".
The government says it shows pylons make economic sense as a 100-mile cable route is planned.
The tax would be applied to manufacturers of milk-based drinks and dairy-based substitutes, under the plans.
The rap group says it does not support Hamas or Hezbollah and would not seek to incite violence against anyone.