Could this kind of trigger effect the standard candle application of Type 1a's? For example, if a black hole triggers a type 1a and that perturbs the type 1a light curve in some way (possibly because less mass could be consumed in the explosion than you would get if one was triggered by mass accretion) and the rate of triggering of this kind changed over time as the universe aged and somehow the population of primordial black holes changed, or the distributions of white dwarf candidates and pbhs changed...

They did some modeling in a previous paper of how this would impact Ia supernovae and it depends on whether the supernova is driven by Kelvin-Helmholtz instabilities or not. In the case that it is, this would only trigger Ia supernovae for white dwarfs which are already very close to the Chandrasekhar mass. In this case the standard candles would be pretty much the same.

In the case that KH instabilities are weaker they claim that you can get supernovae at masses farther from the Chandrasekhar limit. This could plausibly have more of an impact on Ias as standard candles. (Though perhaps less than you might think becauseit would also likely have an effect on the shape of the light curve, and Ias are normalized based on their light curve shape.)

All that said, even if this process does occur, I doubt the rates would be high enough for it to be a substantial fraction of observed Ias.