How are you thinking that decision would be made?
As set out in Section 32 of the Bill.
My understanding is that any decision to allow provision within the NHS in England and Wales rests with the Secretary of State for Health, to introduce through regulations, which are therefore a completely separate decision to the enactment of the Bill itself (were that to happen). And of course the current Secretary of State for Health does not support the Bill so may choose not to bring forward regulations to allow provision within the NHS even if the Bill is passed.
The wording is as follows:
"Provision through NHS etc
32 Secretary of State’s powers to ensure assistance is available
(1) The Secretary of State may, by regulations, make provision—
(a) to secure that arrangements are made, by the Secretary of State or other persons, for the provision of assistance to persons in accordance with this Act, and
(b) for related matters.
(2) Regulations under subsection (1) may, in particular, enable the provision of such assistance as part of the health service in England and the health service in Wales.
(3) The power to make regulations under subsection (1) includes power to amend, repeal or revoke any provision made by an enactment passed or made before the end of the Session in which this Act is passed.
(4) Regulations under subsection (1) are subject to the affirmative procedure."