Bump, because I'd love to know the answer to this too. Jack Straw was another one of the rebellion's leaders, although I have no idea who the other figures are (or if those are even accurate transcriptions of their names in the OP). I semi-sort-of-kind-of hear "Ball and Tyler, all in Leicester, grind-command Jack Straw" but that doesn't make any sense. Any ideas?

Here are the rest of the lyrics:

The men of Kent have met today to put oppression down
And joined with Essex's valiant sons to march on London Town
With Surrey and with Middlesex, with Suffolk, Norfolk too
And gallant lads from Hartfordshire to see the struggle through

With Ball and Tyler...
???????? Jack Straw

From miles around unto Blackheath, the people made there way
And John the priest of Colchester unto us he did say,
"When Adam toiled to win his bread and Mother Eve she spun
All folk were equal one and all and masters there were none"

Say Ball and Tyler...

On Corpus Christi in the morn we gathered at Bankside
Then boldly entered London Town, the gates were opened wide
Oh John of Gaunt that traitor, we burnt his palace down
Threw all his treasure in the flood, yet never took one crown

For Ball and Tyler...

Then to the temple off we went, to flush the lawyers out
We burnt their charters and their books and put them to the rout
They all went scuttling for their lives a-squeaking out with fright
Like imps of hell or sewer rats, it was a wondrous sight

To Ball and Tyler...

Upon the fourteenth day of June the king rode to Mile End
And he spoke softly to us all, "I am the poor man's friend
Your wrongs shall all be righted, all bondsmen be made free"
Oh curse the day we trusted him, for he lied wickedly

To Ball and Tyler...

At Smithfield next we met the King, the nobles gathered round
The Lord Mayor struck a killing blow, Wat Tyler struck the ground
Our masters bared their teeth and smiled to see our hero slain
"You have been slaves since you were born, and slaves you'll now remain"

Ball and Tyler...

The men of England rose to demand their rights
Though they've been dead six hundred years remember them tonight
They raised a flag of liberty, they fought the battle well
They died but others will arise to ring the freedom bell

Like Ball and Tyler...