Creationist sites such as ICR and AIG are renowned for their straight out lying of the science.
I see you have made use of them in your references.
It has been reported that ages up to 3.5 million years were obtained for lava flows that erupted in New Zealand from 1949 to 1975
Here is the true story, the reported dating was done using K-Ar (Potassium-Argon) where the radiometric isotope being measured was Ar-40 (Argon-40).
The Ar-40 in the lava samples was due to atmospheric argon contamination.
Atmospheric argon contains the isotopes Ar-40, Ar-38 and Ar-36, and the presence of Ar-36 in the samples confirmed Ar-40 was an atmospheric contaminant.
K-40 (Potassium 40) has a half-life of around 1.25 billion years and there would not have been enough time for radiogenic Ar-40 to accumulate that would be detectable in the most sensitive mass spectrometers used today.
From another article....The observation that obviously recent lava flows from the north rim of Grand Canyon give ages even older than the deeply buried lava flows, challenges the basic assumptions upon which the isochron dating method is based.
Do you know what an isochron dating method is, evidently ICR doesn’t know either?
For an isochron to be meaningful in this case for Rb-Sr dating, the samples must be of the same age, same initial isotopic ratios and closed-system behaviour after formation.
Given there were separate lava flows and therefore different magma sources it was not an isochron dating method but a pseudo isochron or ‘mixing line’ which gives erroneous ages.
Ten samples from U.S. coal beds, conventionally dated at 40–320 million years old, were found to contain carbon-14 equivalent to ages of around 48,000–50,000 years. The laboratory did repeat analyses and confirmed that this carbon-14 in the coals was not due to any contamination either in situ in the samples or added to the samples in the laboratory.
You creationists should get your stories straight, in fact contamination is the reason why there is a disparity in the ages. Carbon-14 only has a half life of around 50,000 years so after 40-320 million years there is practically nothing remaining to measure.
Like fossils, coal cannot be dated directly only an age range can be given, one method is to use U-Pb (uranium-lead) dating of zircon which allows the accumulation of U but not radiogenic Pb due mainly to different ionic sizes during the crystallization process when magma starts to cool prior to a volcanic eruption.
The deposition of volcanic ash forming layers immediately above and below the coal bed is dated which provides the age range.
Radiometric dating has issues.
This is where the dishonesty of creation sites comes to the fore, problems in radiometric dating are identifiable but like in the examples you have provided the complete picture is deliberately omitted so has to give the impression the problems are not solvable.