did the accountant report each property separately on schedule e for each year. the schedules would then show the total loss and the allowed loss for each. from that you should be able to figure out the unallowed losses for each.
if this doesn't work you have several options,
buy the TT cd's for 2016 and 2017 and redo your returns in sufficient detail so the suspended losses match for each year. a lot of detail is not need totals in most cases will be enough
you could hire another person to redo them but this would be costly
again look at schedule e for 2016, was each property listed separately. if yes ignore any that show a net profit. prorate the suspended losses among the loss properties in proportion to the losses. then do 2017.
if the prior returns submitted by your accountant didn't contain the worksheets showing allocation of the suspended losses then the IRS is going to know either so anything reasonable probably won't cause you future problems.
by the way did you contact the accountant to make sure he didn't have such worksheets.
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