The Opposition is not part of the Government of Trinidad and Tobago: to be part of the Government, one must be a part of the Cabinet!
(2) The Cabinet shall consist of the Prime Minister and such number of other Ministers (of whom one shall be the Attorney General), appointed in accordance with the provisions of section 76, as the Prime Minister may consider appropriate.
76 (3) The Ministers other than the Prime Minister shall be such persons as the President, acting in accordance with the advice of the Prime Minister, shall appoint from among the members of the House of Representatives and the Senators.
79. (1) The President, acting in accordance with the advice of the Prime Minister, may, by directions in writing, assign to the Prime Minister or any other Minister responsibility for any business of the Government of Trinidad and Tobago, including the administration of any department of Government.
81. The Prime Minister shall keep the President fully informed concerning the general conduct of the Government of Trinidad and Tobago and shall furnish the President with such information as he may request with respect to any particular matter relating to the Government of Trinidad and Tobago.
83. (1) There shall be an office of Leader of the Opposition and appointments thereto shall be made by the President.
(2) The President shall, if the person concerned is willing to be appointed, appoint as Leader of the Opposition the member of the House of Representatives who, in his judgement, is best able to command the support of the greatest number of members of the House of Representatives who do not support the Government.
However, being part of Parliament and as Leader of the Opposition, the Leader of the Opposition, through...
Please note the lower-case spelling of the word "government", as compared to upper-case when referring to the Government. Obviously, the difference in casing is not unintentional, for they refer to two different things.
Yes, one may argue that the Leader of the Opposition must be consulted by the President (interestingly, never by the Prime Minister, you hear that, Kamla?) where certain appointments are to be made, however, as far as the author's concerned, every zandolie must find dey hole because of this: the crowning piece to confirm the Leader of the Opposition not being part of the Government is this:
Did you get that? What it says is there is not bound to be a Leader of the Opposition, even though there may be elected Members of Parliament who occupy the opposition benches! So, if Leader of the Opposition is not bound-to-must, then Leader of the Opposition cannot be part of something that bound-to-must.
No need then to write any further, is there?
Read your Constitution! It's accessible online here: http://rgd.legalaffairs.gov.tt/Laws2/Constitution.pdf