Things will be very different when the coalition actually happens. I don't think the IFP are as loyal to the DA as meets the eye. The two have been at odds before.
The VF+, yes and it will be political suicide for them to go into alliance with anyone other than DA as it will be seen as a betrayal to their electorate.
The IFP and Freedom Front are good, the both have a loyal voter base which is very different to ActionSA's, they can afford this. Mashaba's problem is that he still has a party to build, ideally he should be a neutral opposition party that is able to criticise all the parties which are in government, that's how opposition parties grow, stand there and point at the mess and present yourself as a better alternative.
Mashaba cannot do that, he can no longer present himself as an alternative, he cannot tell the people of Tshwane that if they vote for him he will make things better, because he is now part of those who made a mess, he cannot criticise the DA coalition because he is part of the coalition, he can shout at the ANC but the voters will point him back at Tshwane and ask him but what are you doing better where you govern?
Mashaba and his party are slowly drifting into irrelevance and parties like the PA are rising, his funders gives him money but all that is in exchange for him remaining a subservient party to the DA, he is going to accept the DA failings as his own and that's what voters will judge him on.