Found these pink/orangee tinged egg like structures on the soil not attached to plant stems or leaves.. Are in several pots but only those that cardboard plant pots were used.. From internet browsing we are thinking Red Spider Mite but would welcome a full identification, plants affected are Pepper, Tomato and Aubergene.
That feeds mainly on decaying wood, but it can enter living tissue as well.
Tomato is a known host for Nectria cinnabarina (eg. http://www.annualreviews.org/doi/pdf/10.1146/annurev.pp.12.060161.002313). But I think if your plants are growing well and don't develop any lesions from ties, bird or hail damage, etc., they would probably be OK. Nonetheless, I suggest you physcially pick-out the infected lumps of cardboard (or infected woody matter if that is in the compost).