How long was the paint on the model before the tape was applied?
In the past, I have had incidences (usually with Tamiya gloss acrylic) where if the paint isn't fully cured before the tape is applied, it can take on an impression of the tape's texture (rather than actual residue from the tape's adhesive).
The adhesive seems to interact with the underlying paint causing a "ripple-like" effect which resembles a fingerprint. This may be mistaken for residue, but the tape doesn't actually leave anything but an impression behind.