If Republicans want to hear from Hunter Biden, they should take him up on his offer. History tells us witnesses who've met with congressional Republicans behind closed doors have had their comments taken out of context for political purposes. Of course, Republicans will demur because their first public impeachment hearing was an evidence-free embarrassment and this entire probe continues to be a kangaroo court to tarnish the president during election season.
Republicans have been following the money and getting closer to proving the president's corruption, and Hunter Biden shouldn't be able to distract from the evidence by turning his testimony into a spectacle. It's typical procedure to have a deposition — where lawyers can handle the questioning with limited interruptions — and then later possibly have a public hearing. If Hunter Biden has nothing to hide, he will adhere to the subpoena as-is.