The actual number that make their court date is 83%, probably about 90% after accounting for those with excusable absences. I don't see why you should be surprised considering what these people go through to get their day in court.
After getting to the US border which can entail a 2,000 mile or more trip, often walking or hitching which can be a pretty grueling trip particularly for families. Over 70% of Amnesty seekers are families with children. Once they cross the US border and declare they are seeking asylum under the US amnesty legislation, they are given their first amnesty interview. If they pass their 1st interview, they are detained waiting for the 2nd interview and background investigation. This process which is suppose to occur within 2 weeks now it takes 2 to 3 months. If they pass this phase they are scheduled for an amnesty hearing. Currently the wait time is 3 to 4 years. They are given a temporary residents permit and allowed to apply for a temporary work permit which takes about 6 mos.
This first 6 mos can be pretty bad since the housing is often homeless housing, temporary shelters, and goverment or state owned buildings that were never designed for housing. Since they are not allowed to work during this period they can get food stamps and Medicaid. Depending on the state they are in, there are some programs providing some help. Many asylum seekers find they can not make it through the first 6 months and call INS asking for voluntary deportation and cancellation of their court date. This gets them food, shelter and a free trip home. Since deportation is voluntary, they can reapply.
Once asylum seekers get work permits, they and their family can continue to live in the government provided housing if income is below a certain number. However, many of the areas they are housed in become over crowed and INS has to move them. During a 3 year period they may be moved a half dozen times which means finding a new job in a new place they don't know with little or no English. Some will give up and ask for voluntary deportation.
After a few years of this, those that remain are not likey to miss their hearing date because at this point most of them will be accepted into the asylum program which has many benefits including permanent US residency and the ability to apply for US citizenship like any full time resident.
Measuring In Absentia Removal in Immigration Court,” concludes that an
overwhelming 83% of immigrants attend their immigration court hearings, and those who fail to appear in court often did not receive notice or faced hardship in getting to court.