Do you have any examples of the "secret" members?

They must have been shocked when they read this:

So at the General Election in 1945 they returned a Labour Government with a large Parliamentary majority. They rejected the Tories, the party of big business, which had ruled Britain for most of the black years between the wars. They supported the Labour Party, which declared that its aim was peace and friendship with the Soviet Union, and Socialism in Britain.

But instead of the promised friendship with the socialist lands, we have been dragooned into an alliance with the worst enemies of labour—the bankers and business men of America—for war against the countries where the workers are in power.

As a result of this policy, Britain has been dragged into an armaments race; prices are rising while wages are held back; and the workers are now being robbed of the social gains won since the war.

Why has the Labour Government thus failed the hopes of the people? Because far from challenging the rights and privileges of big business at home and abroad, it has allied itself with big business against the people.

It joined hands with the Tories and the American big capitalists in an imperialist foreign policy which is ruining Britain.

The Labour Government has formed a war bloc with American imperialism against the Socialist Soviet Union, the New China, the People’s Democracies and the colonial peoples struggling for their national liberation and independence.

It has conducted wars against the peoples of Malaya and Korea. It has sold out Britain to American big business.

The Labour Government has imposed a crushing rearmament programme for a new war at the expense of the social needs of the people.

The profits of the big trusts and monopolies are higher than they have ever been. Nine-tenths of the wealth of the country is still owned by one-tenth of the population. The sham measures of nationalisation have only increased exploitation and put still heavier burdens on the workers to pay huge sums of compensation to the old owners.

The capitalists have done exceptionally well under the Labour Government; indeed, they have never been better off. The workers have paid for all this in low wages, higher prices and heavier taxation, while the Labour Government has conducted an offensive against the workers’ efforts to secure increased wages. Troops have been used in strikes, hard-won democratic rights have been ruthlessly attacked, strikers have been arrested and prosecuted, and collective bargaining has been turned into a farce by means of Order 1305 and compulsory arbitration.

The talk of Peace and Socialism by the Labour leaders has proved to be a fraud and a deception.

https://www.marxists.org/history/international/comintern/sections/britain/brs/1951/51.htm#1